Old MSVC cannot use Argument Clinic in .cpp files

[zooba]

When adding _wmimodule.cpp (which requires C++ to use some COM APIs), it also used argument clinic.

However, argument clinic uses C++20 features (designated initializers). While we can enable this option with MSVC to use the C++ compiler, this breaks on older versions that are definitely used by buildbots and likely used by some developers.

To work around this, we either stop using clinic for this module, or add a fallback for older MSVC versions.