Merge branch 'master' of https://github.com/bvanassche/fio

* 'master' of https://github.com/bvanassche/fio:
  Introduce enum fio_q_status
  Remove dead code from fio_io_sync()
  gfapi: Make fio_gf_queue() set the I/O unit error status instead of returning -EINVAL
  Change return type of td_io_commit() into void
  Simplify num2str()
  Introduce enum n2s_unit
  Declare stat_calc_lat_nu() static