tests: unskip windows mixing msvc and fortran, for non-gcc fortran

These checked that e.g. the cpp and fc ids are identical, which isn't
strictly what we want. Particularly, msvc doesn't even have a fortran
compiler, and what we really care about is whether we mix both gcc and
something else.

test cases/fortran/14 fortran links c/meson.build

@@ -3,7 +3,9 @@ project('Fortran calling C', 'fortran', 'c',
   default_options : ['default_library=static'])
 
 ccid = meson.get_compiler('c').get_id()
-if ccid == 'msvc' or ccid == 'clang-cl'
+fcid = meson.get_compiler('fortran').get_id()
+
+if fcid == 'gcc' and ccid in ['msvc', 'clang-cl']
   error('MESON_SKIP_TEST: MSVC and GCC do not interoperate like this.')
 endif
 

test cases/fortran/9 cpp/meson.build

@@ -3,7 +3,7 @@ project('C, C++ and Fortran', 'c', 'cpp', 'fortran')
 cpp = meson.get_compiler('cpp')
 fc = meson.get_compiler('fortran')
 
-if build_machine.system() == 'windows' and cpp.get_id() != fc.get_id()
+if build_machine.system() == 'windows' and fc.get_id() == 'gcc' and cpp.get_id() != 'gcc'
   error('MESON_SKIP_TEST mixing gfortran with non-GNU C++ does not work.')
 endif