Work around libselinux API deprecations & auto-sync with upstream branch master
    
    - Add glibc-deprecated-selinux-makedb.patch and
      glibc-deprecated-selinux-nscd.patch to work around libselinux API
      deprecations.
    - Drop glibc-rseq-disable.patch; rseq support removed upstream.
    
    Upstream commit: ec2f1fddf29053957d061dfe310f106388472a4f
    
    - libio: Remove __libc_readline_unlocked
    - shadow: Implement fgetspent_r using __nss_fgetent_r
    - pwd: Implement fgetpwent_r using __nss_fgetent_r
    - gshadow: Implement fgetsgent_r using __nss_fgetent_r (bug 20338)
    - grp: Implement fgetgrent_r using __nss_fgetent_r
    - nss: Add __nss_fgetent_r
    - libio: Add fseterr_unlocked for internal use
    - nss_files: Use generic result pointer in parse_line
    - nss_files: Consolidate line parse declarations in <nss_files.h>
    - nss_compat: Do not use mmap to read database files (bug 26258)
    - nss_files: Consolidate file opening in __nss_files_fopen
    - Update powerpc-nofpu libm-test-ulps.
    - Use MPFR 4.1.0 in build-many-glibcs.py.
    - elf: Change TLS static surplus default back to 1664
    - hurd: Fix longjmp check for sigstate
    - hurd: Fix longjmp early in initialization
    - manual: New signal and errno string functions are AS-safe
    - AArch64: Improve strlen_asimd performance (bug 25824)
    - Move <rpc/netdb.h> from sunrpc to inet
    - en_US: Minimize changes to date_fmt (Bug 25923)
    - Linux: Remove rseq support
    - manual: Use Unicode instead HTML entities for characters (bug 19737)
    - Add NEWS entry for CVE-2020-6096 (bug 25620)
    - arm: remove string/tst-memmove-overflow XFAIL
    - AArch64: Rename IS_ARES to IS_NEOVERSE_N1
    - AArch64: Add optimized Q-register memcpy
    - AArch64: Align ENTRY to a cacheline
    - Correct timespec implementation [BZ #26232]
    - Remove --enable-obsolete-rpc configure flag
    - hurd: Fix build-many-glibcs.py
    - x86: Support usable check for all CPU features
    - string: Make tst-strerror/tst-strsignal unsupported if msgfmt is not installed
    - malloc: Deprecate more hook-related functionality
    - elf: Support at least 32-byte alignment in static dlopen
    - x86: Remove __ASSEMBLER__ check in init-arch.h
    - x86: Remove the unused __x86_prefetchw
    - Documentation for ARC port
    - build-many-glibcs.py: Enable ARC builds
    - ARC: Build Infrastructure
    - ARC: ABI lists
    - ARC: Linux Startup and Dynamic Loading
    - ARC: Linux ABI
    - ARC: Linux Syscall Interface
    - ARC: hardware floating point support
    - ARC: math soft float support
    - ARC: Atomics and Locking primitives
    - ARC: Thread Local Storage support
    - ARC: startup and dynamic linking code
    - ARC: ABI Implementation
    - Fix time/tst-cpuclock1 intermitent failures
    - powerpc64: Fix calls when r2 is not used [BZ #26173]
    - Add NEWS entry for Update to Unicode 13.0.0 [BZ #25819]
    - Update i686 libm-test-ulps
    - Fix memory leak in __printf_fp_l (bug 26215).
    - Fix double free in __printf_fp_l (bug 26214).
    - linux: Fix syscall list generation instructions
    - sysv: linux: Add 64-bit time_t variant for shmctl
    - sysvipc: Remove the linux shm-pad.h file
    - sysvipc: Split out linux struct shmid_ds
    - sysv: linux: Add 64-bit time_t variant for msgctl
    - sysvipc: Remove the linux msq-pad.h file
    - sysvipc: Split out linux struct semid_ds
    - sysv: linux: Add 64-bit time_t variant for semctl