Until this moment carp(4) used a strange logging priority. It used debug
priority for such important information as MASTER/BACKUP state change,
and used a normal logging priority for such innocent messages as receiving
short packet (which is a normal VRRP packet between some other routers) or
receving a CARP packet on non-carp interface (someone else running CARP).

This commit shifts message logging priorities to a more sane default.