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

* 'master' of https://github.com/bvanassche/fio:
  diskutil: Report how many sectors have been read and written
  diskutil: Fix a debug statement in get_io_ticks()
  diskutil: Simplify get_io_ticks()
  diskutil: Remove casts from get_io_ticks()
  diskutil: Improve disk utilization data structure documentation