Auto-sync with upstream branch master
    
    Upstream commit: 6985865bc3ad5b23147ee73466583dd7fdf65892
    
    - elf: Always call destructors in reverse constructor order (bug 30785)
    - io: Fix record locking contants for powerpc64 with __USE_FILE_OFFSET64
    - manual: Fix ld.so diagnostics menu/section structure
    - getaddrinfo: Get rid of alloca
    - riscv: Add support for XTheadBb in string-fz[a,i].h
    - getcanonname: Fix a typo
    - linux: Add pidfd_getpid
    - posix: Add pidfd_spawn and pidfd_spawnp (BZ 30349)
    - linux: Add posix_spawnattr_{get, set}cgroup_np (BZ 26371)
    - linux: Define __ASSUME_CLONE3 to 0 for alpha, ia64, nios2, sh, and sparc
    - __call_tls_dtors: Use call_function_static_weak
    - intl: Treat C.UTF-8 locale like C locale (BZ# 16621)
    - htl: Fix stack information for main thread
    - htl: thread_local destructors support
    - elf: Fix slow tls access after dlopen [BZ #19924]
    - x86: Check the lower byte of EAX of CPUID leaf 2 [BZ #30643]