Remove rsyslog requirement and leave the check of syslog fd availability

Some use syslog-ng instead of rsyslog daemon, this provides the same fd
to communicate with syslog. Instead of hard requirement in spec file, we
leave the check during pre-start and update the output.

Change-Id: I997c6b92b5567b4593fdaf3c7dd33739f59ffb85
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=1083100
Signed-off-by: Yaniv Bronhaim <ybronhei@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/26941
Reviewed-by: Dan Kenigsberg <danken@redhat.com>