totemudpu: Don't block local socketpair

Commit to drop packets from unlisted IPs made ifdown case not working
because msg_name is unset for socketpair.

solution is to drop packets from unlisted IPs only when bind state is
BIND_STATE_REGULAR.

Signed-off-by: Jan Friesse <jfriesse@redhat.com>
Reviewed-by: Christine Caulfield <ccaulfie@redhat.com>