Prevent carp from attaching to other carp interfaces, which the ifp->if_flags & IFF_MULTICAST checks no longer protect against.
Prevent carp from attaching to other carp interfaces, which the
ifp->if_flags & IFF_MULTICAST checks no longer protect against.

ok pascoe@ mpf@

orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars