packaging: updated executing backupDB function

Calling backupDB function from the setup flow
was incorrect. This patch fixes that behavior
by supplying named parameters to the function
and making sure that all the parameters are
correct.

Change-Id: Icef79b53992210c547af13deffd57039fa43e9b0
Bug-Url: https://bugzilla.redhat.com/913176
Signed-off-by: Alex Lourie <alourie@redhat.com>
(cherry picked from commit b8928be5aac72a7267023a66e19e9972341bf2e8)