Including codecapi.h and uuids.h in UWP mode doesn't define all defines
properly, ending up with constructs that MSVC silently tolerates, but
that clang errors out on, like this:
    DEFINE_GUIDEX(CODECAPI_AVEncCommonFormatConstraint);

Just avoid including codecapi.h completely and hardcode the last few
enum values we use from there. We already use local versions of most
enums from there, due to older mingw-w64 headers being incomplete.
Signed-off-by: Martin Storsjö <martin@martin.st>