Auto-sync with upstream branch master
    
    Upstream commit: cf1290064598def8dfeddec3d86d98495aee1fba
    
    - Use the right argument code in unnormal tests
    - ldconfig/x86: Store ISA level in cache and aux cache
    - elf: work around a gcc bug in elf_get_dynamic_info
    - x86: Set header.feature_1 in TCB for always-on CET [BZ #27177]
    - posix: consume less entropy on tempname
    - Makerules: Do not require startup files for format.lds probe object
    - install: Replace scripts/output-format.sed with objdump -f [BZ #26559]
    - math: Add BZ#18980 fix back on dbl-64 cosh
    - posix: Sync tempname with gnulib [BZ #26648]
    - posix: Fix return value of system if shell can not be executed [BZ #27053]
    - support: Add xchmod wrapper
    - Update STATX_ATTR_DAX value from Linux 5.10.
    - riscv: Initialize $gp before resolving the IRELATIVE relocation
    - riscv: support GNU indirect function
    - posix: Correct attribute access mode on readlinkat [BZ #27024].
    -  Add xfchmod to libsupport
    - Add xchdir to libsupport.
    - POSIX locale: Fix typo in comment
    - ARC: Regenerate ulps
    - mntent: Use __putc_unlocked instead of fputc_unlocked
    - aarch64: define PI_STATIC_AND_HIDDEN
    - Update NEWS for CVE-2019-25013.
    - x86: Support GNU_PROPERTY_X86_ISA_1_V[234] marker [BZ #26717]
    - Remove dbl-64/wordsize-64 (part 2)
    - Remove dbl-64/wordsize-64
    - Add SEGV_MTEAERR and SEGV_MTESERR from Linux 5.10.
    - support: Add support_small_thread_stack_size
    - stdlib: Sync canonicalize with gnulib [BZ #10635] [BZ #26592] [BZ #26341] [BZ #24970]
    - malloc: Add scratch_buffer_dupfree
    - Import filename.h from gnulib
    - Import idx.h from gnulib
    - alpha: Provide wait4 for static library [BZ #27150]
    - aarch64: push the set of rules before falling into slow path
    - nptl: Fix comment typo in pthread_cond_wait.c
    - x86: Check IFUNC definition in unrelocated executable [BZ #20019]
    - hurd: Fix mmap(!MAP_FIXED) on bogus address