Auto-sync with upstream branch master
    
    Upstream commit: 75a193b7611bade31a150dfcc528b973e3d46231
    
    - linux: Allow adjtime with NULL argument [BZ #26833]
    - aarch64: Add unwind information to _start (bug 26853)
    - bsd unlockpt: unlockpt needs to fail with EINVAL, not ENOTTY
    - Rearrange bsd_getpt vs bsd_openpt and implement posix_openpt on BSD
    - Remove __warndecl
    - Remove __warn_memset_zero_len [BZ #25399]
    - iconv: Accept redundant shift sequences in IBM1364 [BZ #26224]
    - msg: Remove redundant #include <sys/msg.h> header
    - tst-setuid1-static-ENV: Add $(common-objpfx)nss [BZ #26820]