Auto-sync with upstream branch master,
Upstream commit: e74b61c09a2a2ab52153e731225ccba5078659b1
- Disable -Wstringop-overread for some string tests
- string: Fix GCC 11 `-Werror=stringop-overread' error
- C11 threads: Fix inaccuracies in testsuite
- elf.h: Add aarch64 bti/pac dynamic tag constants
- x86: Set CPU usable feature bits conservatively [BZ #26552]