packaging: spec: upgrade only from >= 3.3.2

Upgrade to 3.4.0 is allowed only from >= 3.3.2.
Avoid to pull in a version of ovirt-engine-setup that will
need to be downgraded in order to allow the upgrade
from a legacy version.

Change-Id: I151c5b1156f4c9a91da0e5bd3e6d52149ae65cd5
Bug-Url: https://bugzilla.redhat.com/1054080
Signed-off-by: Sandro Bonazzola <sbonazzo@redhat.com>