Auto-sync with upstream branch release/2.31/master
    
    Upstream commit: ab029a2801d4ddfeade8f64a6e46ee7e47fde710
    
    - Fix use-after-free in glob when expanding ~user (bug 25414)
    - Update syscall lists for Linux 5.5.
    - NEWS: update list of bugs fixed on the 2.31 branch
    - Add NEWS entry for CVE-2020-10029 (bug 25487)
    - math/test-sinl-pseudo: Use stack protector only if available
    - sparc: Move sigreturn stub to assembly
    - arm: Fix softp-fp Implies (BZ #25635)
    - linux/sysipc: Include linux/posix_types.h for __kernel_mode_t
    - linux: Clear mode_t padding bits (BZ#25623)
    - i386: Use comdat instead of .gnu.linkonce for i386 setup pic register (BZ #20543)
    - Improve IFUNC check [BZ #25506]
    - Avoid ldbl-96 stack corruption from range reduction of pseudo-zero (bug 25487).
    - malloc/tst-mallocfork2: Kill lingering process for unexpected failures
    - riscv: Avoid clobbering register parameters in syscall
    - microblaze: Avoid clobbering register parameters in syscall
    - mips: Fix argument passing for inlined syscalls on Linux [BZ #25523]
    - mips: Use 'long int' and 'long long int' in linux syscall code