bridge: use rx_handler_data pointer to store net_bridge_port pointer

Register net_bridge_port pointer as rx_handler data pointer. As br_port is
removed from struct net_device, another netdev priv_flag is added to indicate
the device serves as a bridge port. Also rcuized pointers are now correctly
dereferenced in br_fdb.c and in netfilter parts.

Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ksz884x.c b/drivers/net/ksz884x.c
index 7805bbf..62362b4 100644
--- a/drivers/net/ksz884x.c
+++ b/drivers/net/ksz884x.c
@@ -5718,7 +5718,7 @@
 		 * from the bridge.
 		 */
 		if ((hw->features & STP_SUPPORT) && !promiscuous &&
-				dev->br_port) {
+		    (dev->priv_flags & IFF_BRIDGE_PORT)) {
 			struct ksz_switch *sw = hw->ksz_switch;
 			int port = priv->port.first_port;