Pyodide build broken by updating meson.build to C17

Scheduled Pyodide build failed today see [build log](https://dev.azure.com/scikit-learn/scikit-learn/_build/results?buildId=66512&view=logs&jobId=6fac3219-cc32-5595-eb73-7f086a643b12&j=6fac3219-cc32-5595-eb73-7f086a643b12&t=6856d197-9931-5ad8-f897-5714e4bdfa31)
```
../meson.build:1:0: ERROR: None of values ['c17'] are supported by the C compiler. Possible values are ['none', 'c89', 'c99', 'c11', 'gnu89', 'gnu99', 'gnu11']
```

This is due to https://github.com/scikit-learn/scikit-learn/pull/28980. Using c11 for example instead of c17 fixes the issue.

Not sure why this is happening and if this is a Pyodide issue or a more generic Meson cross-compilation issue ...

<details>
<summary>Full build log</summary>

```
##[section]Starting: Build Pyodide wheel
==============================================================================
Task         : Bash
Description  : Run a Bash script on macOS, Linux, or Windows
Version      : 3.237.1
Author       : Microsoft Corporation
Help         : https://docs.microsoft.com/azure/devops/pipelines/tasks/utility/bash
==============================================================================
Generating script.
Script contents:
bash build_tools/azure/install_pyodide.sh
========================== Starting Command Output ===========================
[command]/usr/bin/bash /home/vsts/work/_temp/ec9d44b4-19e2-4e87-befe-ff7e5563ae37.sh
Cloning into 'emsdk'...
Resolving SDK version '3.1.46' to 'sdk-releases-21644188d5c473e92f1d7df2f9f60c758a78a486-64bit'
Installing SDK 'sdk-releases-21644188d5c473e92f1d7df2f9f60c758a78a486-64bit'..
Installing tool 'node-16.20.0-64bit'..
Downloading: /home/vsts/work/1/s/emsdk/downloads/node-v16.20.0-linux-x64.tar.xz from https://storage.googleapis.com/webassembly/emscripten-releases-builds/deps/node-v16.20.0-linux-x64.tar.xz, 22559772 Bytes
 [----------------------------------------------------------------------------]
Unpacking '/home/vsts/work/1/s/emsdk/downloads/node-v16.20.0-linux-x64.tar.xz' to '/home/vsts/work/1/s/emsdk/node/16.20.0_64bit'
Done installing tool 'node-16.20.0-64bit'.
Installing tool 'releases-21644188d5c473e92f1d7df2f9f60c758a78a486-64bit'..
Downloading: /home/vsts/work/1/s/emsdk/downloads/21644188d5c473e92f1d7df2f9f60c758a78a486-wasm-binaries.tar.xz from https://storage.googleapis.com/webassembly/emscripten-releases-builds/linux/21644188d5c473e92f1d7df2f9f60c758a78a486/wasm-binaries.tar.xz, 257708108 Bytes
 [----------------------------------------------------------------------------]
Unpacking '/home/vsts/work/1/s/emsdk/downloads/21644188d5c473e92f1d7df2f9f60c758a78a486-wasm-binaries.tar.xz' to '/home/vsts/work/1/s/emsdk/upstream'
Done installing tool 'releases-21644188d5c473e92f1d7df2f9f60c758a78a486-64bit'.
Done installing SDK 'sdk-releases-21644188d5c473e92f1d7df2f9f60c758a78a486-64bit'.
Resolving SDK version '3.1.46' to 'sdk-releases-21644188d5c473e92f1d7df2f9f60c758a78a486-64bit'
Setting the following tools as active:
   node-16.20.0-64bit
   releases-21644188d5c473e92f1d7df2f9f60c758a78a486-64bit

Next steps:
- To conveniently access emsdk tools from the command line,
  consider adding the following directories to your PATH:
    /home/vsts/work/1/s/emsdk
    /home/vsts/work/1/s/emsdk/upstream/emscripten
- This can be done for the current shell by running:
    source "/home/vsts/work/1/s/emsdk/emsdk_env.sh"
- Configure emsdk in your shell startup scripts by running:
    echo 'source "/home/vsts/work/1/s/emsdk/emsdk_env.sh"' >> $HOME/.bash_profile
Setting up EMSDK environment (suppress these messages with EMSDK_QUIET=1)
Adding directories to PATH:
PATH += /home/vsts/work/1/s/emsdk
PATH += /home/vsts/work/1/s/emsdk/upstream/emscripten

Setting environment variables:
PATH = /home/vsts/work/1/s/emsdk:/home/vsts/work/1/s/emsdk/upstream/emscripten:/opt/hostedtoolcache/Python/3.11.3/x64/bin:/opt/hostedtoolcache/Python/3.11.3/x64:/snap/bin:/home/vsts/.local/bin:/opt/pipx_bin:/home/vsts/.cargo/bin:/home/vsts/.config/composer/vendor/bin:/usr/local/.ghcup/bin:/home/vsts/.dotnet/tools:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games
EMSDK = /home/vsts/work/1/s/emsdk
EMSDK_NODE = /home/vsts/work/1/s/emsdk/node/16.20.0_64bit/bin/node
/home/vsts/work/1/s
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Installing collected packages: resolvelib, leb128, distlib, wheel, urllib3, typing-extensions, tomli, sniffio, shellingham, ruamel.yaml.clib, pyyaml, pyproject_hooks, pygments, platformdirs, packaging, mdurl, idna, h11, filelock, cython, cmake, cloudpickle, click, charset-normalizer, certifi, virtualenv, types-requests, ruamel.yaml, requests, pydantic, markdown-it-py, loky, httpcore, build, anyio, rich, pyodide-lock, httpx, unearth, typer, pyodide-cli, auditwheel-emscripten, pyodide-build
Successfully installed anyio-4.3.0 auditwheel-emscripten-0.0.14 build-1.2.1 certifi-2024.2.2 charset-normalizer-3.3.2 click-8.1.7 cloudpickle-3.0.0 cmake-3.29.3 cython-0.29.37 distlib-0.3.8 filelock-3.14.0 h11-0.14.0 httpcore-1.0.5 httpx-0.27.0 idna-3.7 leb128-1.0.7 loky-3.4.1 markdown-it-py-3.0.0 mdurl-0.1.2 packaging-24.0 platformdirs-4.2.1 pydantic-1.10.15 pygments-2.18.0 pyodide-build-0.25.1 pyodide-cli-0.2.3 pyodide-lock-0.1.0a4 pyproject_hooks-1.1.0 pyyaml-6.0.1 requests-2.31.0 resolvelib-1.0.1 rich-13.7.1 ruamel.yaml-0.18.6 ruamel.yaml.clib-0.2.8 shellingham-1.5.4 sniffio-1.3.1 tomli-2.0.1 typer-0.12.3 types-requests-2.31.0.20240406 typing-extensions-4.11.0 unearth-0.15.2 urllib3-2.2.1 virtualenv-20.26.2 wheel-0.43.0
Downloading xbuild environment                                                  
Installing xbuild environment                                                   
+ meson setup /home/vsts/work/1/s /home/vsts/work/1/s/.mesonpy-h6vlcfoy -Dbuildtype=release -Db_ndebug=if-release -Db_vscrt=md --native-file=/home/vsts/work/1/s/.mesonpy-h6vlcfoy/meson-python-native-file.ini
The Meson build system
Version: 1.4.0
Source dir: /home/vsts/work/1/s
Build dir: /home/vsts/work/1/s/.mesonpy-h6vlcfoy
Build type: cross build
Project name: scikit-learn
Project version: 1.6.dev0
Cross compiler sanity tests disabled via the cross file.

../meson.build:1:0: ERROR: None of values ['c17'] are supported by the C compiler. Possible values are ['none', 'c89', 'c99', 'c11', 'gnu89', 'gnu99', 'gnu11']

A full log can be found at /home/vsts/work/1/s/.mesonpy-h6vlcfoy/meson-logs/meson-log.txt

ERROR Backend subprocess exited when trying to invoke build_wheel

##[error]Bash exited with code '1'.
##[section]Finishing: Build Pyodide wheel
```

</details>

COMMENT:
Re-reading https://github.com/scikit-learn/scikit-learn/issues/28977#issue-2285953337 carefully it says 
> CPython itself is built with C11, which is a superset of C17.

So I guess C11 should be good enough for CPython? Pyodide seems to builds fine with C11 locally. I opened https://github.com/scikit-learn/scikit-learn/pull/29015 to see whether the Pyodide tests pass in the CI with c11.

Labels: Bug, Build / CI, free-threading