Repository: mesonbuild/meson

Issue:
regression: {intel,intel-cl} compilers for Fortran
**Describe the bug**

Intel / Intel-CL  (Windows, Linux) compilers broken on master for Fortran language. I checked GCC and PGI and they were still OK.

2844afedde3992564e0de4538b29781a420f8576 is the first bad commit

All the Fortran project tests run by

```sh
python run_project_tests.py --only fortran
```
fail like

```Main binary: C:\miniconda3\python.exe
Build Options: -Dprefix=x:/usr -Dlibdir=lib -Dbackend=ninja
Python system: Windows
The Meson build system
Version: 0.56.99
Source dir: meson\test cases\fortran\1 basic
Build dir: meson\b 51404b66cd
Build type: native build
Project name: simple fortran
Project version: undefined
None of 'FC' are defined in the environment, not changing global flags.
None of 'FFLAGS' are defined in the environment, not changing global flags.
None of 'LDFLAGS' are defined in the environment, not changing global flags.
Fortran compiler for the host machine: ifort (intel-cl 2021.1)
Fortran linker for the host machine: xilink.exe xilink 2021.1
None of 'AR' are defined in the environment, not changing global flags.
None of 'FC' are defined in the environment, not changing global flags.
None of 'FFLAGS' are defined in the environment, not changing global flags.
None of 'LDFLAGS' are defined in the environment, not changing global flags.
Fortran compiler for the build machine: ifort (intel-cl 2021.1)
Fortran linker for the build machine: xilink.exe xilink 2021.1
None of 'AR' are defined in the environment, not changing global flags.

test cases\fortran\1 basic\meson.build:1:0: ERROR: Value "none" (of type "string") for combo option "Fortran language standard to use" is not one of the choices. Possible choices are (as string): "legacy", "f95", "f2003", "f2008", "f2018".
```

test cases/common/30 compiler id fails similarly:
```
The Meson build system
Version: 0.56.99
Source dir: meson\test cases\common\30 compiler id
Build dir: meson\test cases\common\30 compiler id\build
Build type: native build
Project name: compiler_id
Project version: undefined
Host machine cpu family: x86_64
Host machine cpu: x86_64
C compiler for the host machine: icl (intel-cl 2021.1)
C linker for the host machine: xilink.exe xilink 2021.1
Message: c compiler name is: intel-cl
Message: c linker name is: xilink
C++ compiler for the host machine: icl (intel-cl 2021.1)
C++ linker for the host machine: xilink.exe xilink 2021.1
Message: cpp compiler name is: intel-cl
Message: cpp linker name is: xilink
Fortran compiler for the host machine: ifort (intel-cl 2021.1)
Fortran linker for the host machine: xilink.exe xilink 2021.1

meson.build:5:9: ERROR: Value "none" (of type "string") for combo option "Fortran language standard to use" is not one of the choices. Possible choices are (as string): "legacy", "f95", "f2003", "f2008", "f2018".

A full log can be found at meson\test cases\common\30 compiler id\build\meson-logs\meson-log.txt
```

**To Reproduce**
```sh
python run_project_tests.py --only fortran
```
using Intel oneAPI 2021.1 on **Linux** or **Windows** (didn't try Mac)


**system parameters**
* usual native build
* Windows 10 or Linux
* Python 3.8.5
* ninja 1.10.1



Discussion:

Resolving patch:
diff --git a/mesonbuild/compilers/fortran.py b/mesonbuild/compilers/fortran.py
--- a/mesonbuild/compilers/fortran.py
+++ b/mesonbuild/compilers/fortran.py
@@ -315,7 +315,7 @@ def __init__(self, exelist: T.List[str], version: str, for_machine: MachineChoic
 
     def get_options(self) -> 'OptionDictType':
         opts = FortranCompiler.get_options(self)
-        opts['std'].choices = ['legacy', 'f95', 'f2003', 'f2008', 'f2018']  # type: ignore
+        opts['std'].choices = ['none', 'legacy', 'f95', 'f2003', 'f2008', 'f2018']  # type: ignore
         return opts
 
     def get_option_compile_args(self, options: 'OptionDictType') -> T.List[str]:
@@ -365,7 +365,7 @@ def __init__(self, exelist: T.List[str], version: str, for_machine: MachineChoic
 
     def get_options(self) -> 'OptionDictType':
         opts = FortranCompiler.get_options(self)
-        opts['std'].choices = ['legacy', 'f95', 'f2003', 'f2008', 'f2018']  # type: ignore
+        opts['std'].choices = ['none', 'legacy', 'f95', 'f2003', 'f2008', 'f2018']  # type: ignore
         return opts
 
     def get_option_compile_args(self, options: 'OptionDictType') -> T.List[str]:


Test patch: