Don't hide -msse and -mfpu=neon checks behind a not-msvc check
Don't hide -msse and -mfpu=neon checks behind a not-msvc check

Apparently Clang gets reported as being MSVC on Windows, but still needs the
GCC switches to enable SSE code generation.

aaronmjacobs/openal-soft,aaronmjacobs/openal-soft