engine: Removing flood message from engine.log

The following message is written to engine.log when
we are trying to add some audit log message and it is illegal - meaning it should
be skipped, the message is misleading and also for case of very common event
we just flooding engine.log

Change-Id: I0ec84555c0473a2e051d68f27cbbbbbd84fa6c9a
Signed-off-by: Michael Kublin <mkublin@redhat.com>