LU-1842 test: remove code from s-q to use OFD

LU-1842 test: remove code from s-q to use OFD

Now that obdfilter is gone and OFD is the default, we don't need to
restart lustre with USE_OFD any more.

Signed-off-by: Johann Lombardi <johann.lombardi@intel.com>
Change-Id: Ifa3647bd815866aa29bd88a9b3c6be16c6c66fa5
Reviewed-on: http://review.whamcloud.com/4222
Reviewed-by: Niu Yawei <niu@whamcloud.com>
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Li Wei <liwei@whamcloud.com>
Reviewed-by: Yu Jian <yujian@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>