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/net/mac80211/rx.c b/net/mac80211/rx.c
index 6e2a7bc..2d9a2ee 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -2139,7 +2139,7 @@
 		u8 rate_or_pad;
 		__le16 chan_freq;
 		__le16 chan_flags;
-	} __attribute__ ((packed)) *rthdr;
+	} __packed *rthdr;
 	struct sk_buff *skb = rx->skb, *skb2;
 	struct net_device *prev_dev = NULL;
 	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(skb);