test/ocf: disable norandommap flag

disable FIO norandommap flag because it is incompatible with
  verify which in context of async IO could cause verification errors.
More on norandommap:
  https://fio.readthedocs.io/en/latest/fio_doc.html#cmdoption-arg-norandommap



Change-Id: I94392495a1f9f06360e3791fca31b88908d19dcb
Signed-off-by: Vitaliy Mysak <vitaliy.mysak@intel.com>
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/457001


Reviewed-by: Darek Stojaczyk <dariusz.stojaczyk@intel.com>
Reviewed-by: Tomasz Zawadzki <tomasz.zawadzki@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>