bridge: add RCU annotations to bridge port lookup

br_port_get() renamed to br_port_get_rtnl() to make clear RTNL is held.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/bridge/br_notify.c b/net/bridge/br_notify.c
index ef2175c..7d337c9 100644
--- a/net/bridge/br_notify.c
+++ b/net/bridge/br_notify.c
@@ -37,10 +37,10 @@
 	int err;
 
 	/* not a port of a bridge */
-	if (!br_port_exists(dev))
+	p = br_port_get_rtnl(dev);
+	if (!p)
 		return NOTIFY_DONE;
 
-	p = br_port_get(dev);
 	br = p->br;
 
 	switch (event) {