Merge branch 'macos-prep' of https://github.com/t-8ch/util-linux

* 'macos-prep' of https://github.com/t-8ch/util-linux:
  meson: gate schedutils behind its requirements
  meson: gate write on _PATH_UTMP
  meson: gate agetty on _PATH_UTMP
  meson: gate pipesz on F_GETPIPE_SZ
  meson: gate sulogin on shadow.h
  meson: gate switch_root on sys/statfs.h
  meson: gate nsenter on sys/statfs.h
  meson: gate uuidd on sys/signalfd.h
  meson: gate fincore on LINUX
  meson: add build-fincore option
  meson: gate prlimit on prlimit()
  meson: add build-prlimit option
  meson: gate wdctl on linux/watchdog.h
  meson: respect build-wdctl