Auto-sync with upstream branch master
    
    Upstream commit: 78fb88827362fbd2cc8aa32892ae5b015106e25c
    
    - mips: Fix mips64n32 64 bit time_t stat support (BZ#29069)
    - x86: Cleanup page cross code in memcmp-avx2-movbe.S
    - x86: Remove memcmp-sse4.S
    - x86: Optimize memcmp SSE2 in memcmp.S
    - misc: Use 64 bit time_t interfaces on syslog
    - misc: syslog: Move SYSLOG_NAME to USE_MISC (BZ #16355)
    - misc: syslog: Use fixed-sized buffer and remove memstream
    - misc: syslog: Simplify implementation
    - misc: syslog: Fix indentation and style
    - misc: Add syslog test
    - support: Add xmkfifo
    - stdio: Split __get_errname definition from errlist.c
    - x86: Reduce code size of mem{move|pcpy|cpy}-ssse3
    - x86: Remove mem{move|cpy}-ssse3-back
    - x86: Remove str{p}{n}cpy-ssse3
    - x86: Remove str{n}cat-ssse3
    - x86: Remove str{n}{case}cmp-ssse3
    - x86: Remove {w}memcmp-ssse3
    - nptl: Handle spurious EINTR when thread cancellation is disabled (BZ#29029)
    - S390: Add new s390 platform z16.
    - Replace {u}int_fast{16|32} with {u}int32_t
    - stdlib: Reflow and sort most variable assignments
    - elf: Fix memory leak in _dl_find_object_update (bug 29062)
    - hurd: Define ELIBEXEC
    - hurd: Fix arbitrary error code
    - NEWS: Move PLT tracking slowdown to glibc 2.35.
    - Remove _dl_skip_args_internal declaration
    - test-container: Fix "unused code" warnings on HURD
    - Add .clang-format style file
    - manual: Avoid name collision in libm ULP table [BZ #28956]