[PATCH net-next 1/2] bridge: prevent flooding IPv6 packets that do not have a listener

Currently if there is no listener for a certain group then IPv6 packets for that group are flooded on all ports, even though there might be no host and router interested in it on a port. With this commit they are only forwarded to ports with a multicast router. Just like commit bd4265fe36

[PATCH net-next 1/2] bridge: prevent flooding IPv6 packets that do not have a listener

Currently if there is no listener for a certain group then IPv6 packets for that group are flooded on all ports, even though there might be no host and router interested in it on a port. With this commit they are only forwarded to ports with a multicast router. Just like commit bd4265fe36