Auto-sync with upstream branch master
    
    Upstream commit: ec138c67cbda8b5826a0a2a7ba456408117996dc
    
    - sysdeps: Add clock_gettime64 vDSO
    - Do not use ld.so to open statically linked programs in debugglibc.sh
    - Attach to test in container from debugglibc.sh
    - Expand $(as-needed) and $(no-as-needed) throughout the build system
    - x86: Assume --enable-cet if GCC defaults to CET [BZ #25225]
    - ldbl-128ibm-compat: Add tests for strfroml, strtold, and wcstold
    - ldbl-128ibm-compat: Add tests for strfmon and strfmon_l
    - ldbl-128ibm-compat: Add strfmon_l with IEEE long double format
    - ldbl-128ibm-compat: Replace http with https in new files
    - elf: Do not run IFUNC resolvers for LD_DEBUG=unused [BZ #24214]
    - elf/tst-dlopenfail: Disable --no-as-needed for tst-dlopenfailmod1.so
    - hurd: Fix ld.so __access override from libc
    - hurd: Fix ld.so __getcwd override from libc
    - hurd: Make __sigprocmask GLIBC_PRIVATE
    - hurd: Fix renameat2 error
    - hurd: make strerror(0) coherent with other ports
    - hurd: Fix ld.so link
    - Update kernel version to 5.4 in tst-mman-consts.py.
    - Update SOMAXCONN value from Linux 5.4.
    - Update syscall-names.list for Linux 5.4.
    - Fix syntax error in build-many-glibcs.py.
    - Define MADV_COLD and MADV_PAGEOUT from Linux 5.4.