net/802: add __rcu annotations

(struct net_device)->garp_port is rcu protected :
(struct garp_port)->applicants is rcu protected :

add __rcu annotation and proper rcu primitives.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 4722d4a..b72d5a4 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1072,7 +1072,7 @@
 		struct pcpu_dstats __percpu	*dstats; /* dummy stats */
 	};
 	/* GARP */
-	struct garp_port	*garp_port;
+	struct garp_port __rcu	*garp_port;
 
 	/* class/net/name entry */
 	struct device		dev;