packaging: Use engine.conf for local configuration

Commit 5a3141 of ovirt-engine moved the local configuration from
/etc/sysconfig/ovirt-engine to /etc/ovirt-engine/engine.conf so DWH
needs to be modified accordingly.

Change-Id: Ifb3ba0ae3c9f9d24782d4d55f99836bf157800ec
Signed-off-by: Juan Hernandez <juan.hernandez@redhat.com>