net: use __packed annotation

cleanup patch.

Use new __packed annotation in net/ and include/
(except netfilter)

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/ip6_tunnel.h b/include/net/ip6_tunnel.h
index fbf9d1c..fc94ec5 100644
--- a/include/net/ip6_tunnel.h
+++ b/include/net/ip6_tunnel.h
@@ -27,6 +27,6 @@
 	__u8 type;		/* type-code for option         */
 	__u8 length;		/* option length                */
 	__u8 encap_limit;	/* tunnel encapsulation limit   */
-} __attribute__ ((packed));
+} __packed;
 
 #endif