packaging: /etc/ovirt-engine/engine.conf* should not be owned by engine

engine does not and should not write into it.

if there is secret configuration it can be explicitly written owned by
engine.

Change-Id: I6d9ca270bd1d3a16591a3d4fae65bbaac65c8654
Signed-off-by: Alon Bar-Lev <alonbl@redhat.com>