LU-8702 tests: parallel execution of IOR and MDTEST added.

LU-8702 tests: parallel execution of IOR and MDTEST added.

Added test case for execution of mdtest and IOR in parallel.

Test-Parameters: trivial testlist=parallel-scale
Change-Id: I3b8a74a94739417467cc04bcc5e688b487d0cfe7
Seagate-bug-id: MRP-3149
Signed-off-by: Ashish Maurya <ashish.maurya@seagate.com>
Signed-off-by: Aditya Pandit <aditya.pandit@seagate.com>
Reviewed-on: http://es-gerrit.xyus.xyratex.com:8080/10376
Tested-by: Jenkins
Reviewed-by: Alexander Lezhoev <alexander.lezhoev@seagate.com>
Reviewed-by: Rahul Deshmukh <rahul.deshmukh@seagate.com>
Reviewed-by: Ujjwal Lanjewar <ujjwal.lanjewar@seagate.com>
Tested-by: Elena V. Gryaznova <elena.gryaznova@seagate.com>
Reviewed-on: https://review.whamcloud.com/23126
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: James Nunez <james.a.nunez@intel.com>
Reviewed-by: Elena Gryaznova <elena.gryaznova@seagate.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>