Merge branch 'io-uring-cmd/nvme/add-flush' of https://github.com/minwooim/fio

* 'io-uring-cmd/nvme/add-flush' of https://github.com/minwooim/fio:
  t/nvmept.py: Add test cases for FLUSH
  io_u: Support fsync for --rw=trimwrite
  io_u: Ensure fsync only after write(s)
  td: Replace last_was_sync with last_ddir_issued
  td: Rename last_ddir to last_ddir_completed
  io_uring: Add support FLUSH command