packaging: setup: fix updating pg_hba.conf

pg_hba.conf was not updated correctly e.g. on upgrade from 3.2.

Change-Id: I6b07a19245957a4bd8c2cd6dd3fc7d1a5b64610b
Bug-Url: https://bugzilla.redhat.com/1121644
Signed-off-by: Yedidyah Bar David <didi@redhat.com>