Fix the build.
Merge branch 'master' of github.com:mono/mono into symform-3-0
[xbuild]: Allow expressions inside a dynamic <ItemGroup>'s metadata.

Fixes #14661.
[xbuild]: Provide diagnostic logging of all executed targets.
[xbuild]: Check a <Target>'s "Returns" first, then fall-back to "Outputs".

This fixes a problem with the "Microsoft.Bcl.Build" NuGet package, which
overrides the "GetTargetPath" target in a custom .targets file and uses
"Returns" instead of "Outputs".
Fixed missing pointer conversion tests in sizes.c

Unsigned pointer conversion was not tested at all (looks like a copy & paste mistake)
[sgen] Link unit test programs with all libs.

Should fix the build for monodroid.
[corlib] Update CurrentRegion to work with DefaultThreadCurrentCulture
Remove some more mdb bits.
[corlib] CreateSpecificCulture without exception retry
Unbreak libgc.
Merge pull request #824 from hanswolff/patch-1

Fixed missing pointer conversion tests in sizes.c
Fix a warning on PPC.
Fix more PPC warnings.
Fix a couple of warnings in mini-exceptions.c.
Fix some warnings in mini-amd64.c.
[corlib] Better conversion betwen system locale and CultureInfo. Fixes #15875
Fix some warnings caused by always_inline functions not being marked inline.
Add a dummy assignment to shut GCC up.
Fix some pointer/integer size issues in unwind.c on 32-bit systems.