linux: add missing pthread_attr_setstack

[terohuttunen]

Description

This PR adds the missing pthread_attr_setstack function for linux-like architectures. The getter pthread_attr_getstack is already defined.

Sources

• pthread_attr_setstack man page
• https://github.com/bminor/glibc/blob/c6e2895695118ab59c7b17feb0fcb75a53e3478c/sysdeps/htl/pthread.h#L158
• https://github.com/kraj/musl/blob/1880359b54ff7dd9f5016002bfdae4b136007dde/include/pthread.h#L159
• https://github.com/emscripten-core/emscripten/blob/14193a094b8b6668d28bb82527e616ab327fae7b/system/lib/libc/musl/src/thread/pthread_attr_setstack.c#L3
• https://cs.android.com/android/platform/superproject/main/+/main:bionic/libc/include/pthread.h;l=124;drc=1960f1c7dcd60b29628bc96717a98efaad9e6c64

Checklist

• Relevant tests in libc-test/semver have been updated
• No placeholder or unstable values like *LAST or *MAX are
  included (see #3131)
• Tested locally (cd libc-test && cargo test --target mytarget);
  especially relevant for platforms that may not be checked in CI

[rustbot]

r? @tgross35

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[tgross35]

Added permalinks to the headers to the description. Thanks!

@rustbot label +stable-nominated