Merge branch 'atomic-writes'

Merge the atomc write support.

* atomic-writes:
  examples: Add example for atomic write verify
  fio: Support verify_write_sequence
  doc: Document atomic command
  tools/fiograph: Update for atomic support
  io_uring: Support RWF_ATOMIC
  libaio: Support RWF_ATOMIC
  pvsync2: Support RWF_ATOMIC
  os: Reintroduce atomic write support
  os-linux: Define RWF_ATOMIC