packaging: engine-backup: Log tar creation failures
packaging: engine-backup: Log tar creation failures

Change-Id: I39df58b46fff2e34b04a3d6255bc265006c94031
Signed-off-by: Yedidyah Bar David <e7f2f616ce8817ad893bbeaad3e942e94c69d323@redhat.com>

OpenUniversity/ovirt-engine,OpenUniversity/ovirt-engine,OpenUniversity/ovirt-engine,OpenUniversity/ovirt-engine,OpenUniversity/ovirt-engine