LU-1410 test: Allow sanity test 200 to work with one OST

LU-1410 test: Allow sanity test 200 to work with one OST

The sanity test is failing test 200 with one OST. When
the test adds machines to the pool it is not passing
valid arguments.

Changing first_ost=0 is allowing the test to run.

Signed-off-by:Keith Mannthey <keith@whamcloud.com>
Change-Id: I45aef14e7814f170024c71f904b888423d8f8c90
Reviewed-on: http://review.whamcloud.com/3730
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Minh Diep <mdiep@whamcloud.com>
Reviewed-by: Yu Jian <yujian@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>