packaging: services: ovirt-engine: enforce log level for server.log

due to unknown reason there was report that server.log was put into
debug level.

so let's be consistent and enforce its level as well.

Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=1021346
Change-Id: Id1ec5786ef64986e38e3766b2aabd22f5e544225
Signed-off-by: Alon Bar-Lev <alonbl@redhat.com>