bridge: Add netlink interface to configure vlans on bridge ports

Add a netlink interface to add and remove vlan configuration on bridge port.
The interface uses the RTM_SETLINK message and encodes the vlan
configuration inside the IFLA_AF_SPEC.  It is possble to include multiple
vlans to either add or remove in a single message.

Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/bridge/br_device.c b/net/bridge/br_device.c
index 35a2c2c..091bedf 100644
--- a/net/bridge/br_device.c
+++ b/net/bridge/br_device.c
@@ -316,6 +316,7 @@
 	.ndo_fdb_dump		 = br_fdb_dump,
 	.ndo_bridge_getlink	 = br_getlink,
 	.ndo_bridge_setlink	 = br_setlink,
+	.ndo_bridge_dellink	 = br_dellink,
 };
 
 static void br_dev_free(struct net_device *dev)