[sanitizer] Change NanoTime to use clock_gettime on non-glibc

This avoids the `__NR_gettimeofday` syscall number, which does not exist on 32-bit musl (it has `__NR_gettimeofday_time32`).

This switched Android to `clock_gettime` as well, which should work according to the old code before D96925.

Tested on Alpine Linux x86-64 (musl) and FreeBSD x86-64.

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D98121