Rollup merge of #151403 - joboet:clock_nanosleep_time64, r=Mark-Simulacrum

std: use 64-bit `clock_nanosleep` on GNU/Linux if available

glibc 2.31 added support for both 64-bit `clock_gettime` and 64-bit `clock_nanosleep`. Thus, if [`__clock_nanosleep_time64`](https://sourceware.org/git/?p=glibc.git;a=blob;f=include/time.h;h=22b29ca583549488a0e5395cb820f55ec6e38e5f;hb=e14a91e59d35bf2fa649a9726ccce838b8c6e4b7#l322) and the underlying syscall are available, use them for implementing `sleep_until` to avoid having to fall back to `nanosleep` for long-duration sleeps.

Author: matthiaskrgr