LU-11169 obdclass: fix old return code usage

LU-11169 obdclass: fix old return code usage

Commit 49d8a7ccd73 from LU-9855 introduce a fail in the
obd_commitrw function which parent error code
replaced with result of exp_check_ops function.

Cray-bugid: LUS-6195

Test-Parameters: trivial
Change-Id: If8643ba39232f94ba9c523fdb9f10c1411a1838a
Signed-off-by: Alexey Lyashkov <c17817@cray.com>
Reviewed-on: https://review.whamcloud.com/32906
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: James Simmons <uja.ornl@yahoo.com>
Reviewed-by: Ben Evans <bevans@cray.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>