Merge branch 'readonly-trim' of https://github.com/vincentkfu/fio

* 'readonly-trim' of https://github.com/vincentkfu/fio:
  testing: add test script for readonly parameter
  doc: improve readonly option description
  options: check for conflict between trims and readonly option
  init: abort write and trim jobs when --readonly option is present
  init: ensure that fatal errors in fixup_options are always propogated to caller
  filesetup: make trim jobs respect --readonly during file open
  fio.h: also check trim operations in fio_ro_check