packaging: setup: unset DisconnectDwh on failure

Change-Id: I09083bc79ead4711a7a998fab112c58ef80b0b4d
Bug-Url: https://bugzilla.redhat.com/1168160
Signed-off-by: Yedidyah Bar David <didi@redhat.com>
(cherry picked from commit 7348799e9dcd38b5bc974debaa96be85d116c559)