Auto-sync with upstream branch master
    
    Upstream commit: 8e28aa3a51bf0ef3683f2aed4b5b448744897b66
    
    - elf: Remove fallback to the start of DT_STRTAB for dladdr
    - powerpc32: Remove unused HAVE_PPC_SECURE_PLT
    - dlfcn: Implement the RTLD_DI_PHDR request type for dlinfo
    - manual: Document the dlinfo function
    - Do not use --hash-style=both for building glibc shared objects
    - benchtests: Better libmvec integration
    - benchtests: Add UNSUPPORTED benchmark status
    - linux: Fix fchmodat with AT_SYMLINK_NOFOLLOW for 64 bit time_t (BZ#29097)
    - Use __ehdr_start rather than _begin in _dl_start_final
    - sysdeps: Add 'get_fast_jitter' interace in fast-jitter.h
    - posix/glob.c: update from gnulib
    - benchtests: Add pthread-mutex-locks bench
    - linux: Fix missing internal 64 bit time_t stat usage
    - elf: Fix DFS sorting algorithm for LD_TRACE_LOADED_OBJECTS with missing libraries (BZ #28868)
    - posix: Remove unused definition on _Fork
    - NEWS: Mention DT_RELR support
    - elf: Add more DT_RELR tests
    - elf: Properly handle zero DT_RELA/DT_REL values
    - elf: Support DT_RELR relative relocation format [BZ #27924]
    - Add GLIBC_ABI_DT_RELR for DT_RELR support
    - elf: Define DT_RELR related macros and types
    - elf: Replace PI_STATIC_AND_HIDDEN with opposite HIDDEN_VAR_NEEDS_DYNAMIC_RELOC
    - i386: Regenerate ulps
    - dlfcn: Do not use rtld_active () to determine ld.so state (bug 29078)
    - INSTALL: Rephrase -with-default-link documentation