bridge: update vlan dev state when port added to or deleted from vlan

If vlan bridge binding is enabled, then the link state of a vlan device
that is an upper device of the bridge should track the state of bridge
ports that are members of that vlan. So if a bridge port becomes or
stops being a member of a vlan, then update the link state of the
vlan device if necessary.

Signed-off-by: Mike Manning <mmanning@vyatta.att-mail.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>