[libc] Fix fexcept_t type to match canonical ABI and API (#113666)

In glibc and musl, fexcept_t is unsigned short int on x86 and
unsigned int on other machines that llvm-libc supports.  Match
that ABI (only different from before on x86) and API (different
everywhere as it was previously signed).

GitOrigin-RevId: 0c8e12fc64073a889956e790881cdf0d58018372
1 file changed