[X86] Make -mavx512f imply -mfma and -mf16c in the frontend like it
does in the backend.

Similarly, make -mno-fma and -mno-f16c imply -mno-avx512f.

Withou this  "-mno-sse -mavx512f" ends up with avx512f being enabled
in the frontend but disabled in the backend.