Auto-sync with upstream branch master
    
    Upstream commit: 271ec55d0ae795f03d92e3aa61bff69a31a19e3a
    
    - support: Do not build xpthread_attr_setaffinity_np for hurd
    - nptl: Add pthread_attr_setaffinity_np failure test
    - support: Add xpthread_attr_setaffinity_np wrapper
    - nptl: Move createthread to pthread_create
    - nptl: Move Linux createthread to nptl
    - nptl: Install SIGSETXID handler with SA_ONSTACK [BZ #27914]
    - aarch64: Added optimized memset for A64FX
    - aarch64: Added optimized memcpy and memmove for A64FX
    - benchtests: Fixed bench-memcpy-random: buf1: mprotect failed
    - aarch64: Added Vector Length Set test helper script
    - aarch64: define BTI_C and BTI_J macros as NOP unless HAVE_AARCH64_BTI
    - config: Added HAVE_AARCH64_SVE_ASM for aarch64
    - tst-mallinfo2.c: Use correct multiple for total variable