packaging: engine-setup should allow the minumum shmmax

engine-setup should allow the minimun shmmax defined.

Change-Id: I2fc14ddd29c0aca7f3f5712ac176b50d55785b2a
Signed-off-by: Ofer Schreiber <oschreib@redhat.com>
Bug-Url: https://bugzilla.redhat.com/1059355
(cherry picked from commit 0a88c4b88d5f3edbd707b0252ec13e30217c9938)