[NET]: Kill skb->real_dev

Bonding just wants the device before the skb_bond()
decapsulation occurs, so simply pass that original
device into packet_type->func() as an argument.

It remains to be seen whether we can use this same
exact thing to get rid of skb->input_dev as well.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/arp.h b/include/net/arp.h
index a1f09fa..a13e30c 100644
--- a/include/net/arp.h
+++ b/include/net/arp.h
@@ -11,7 +11,7 @@
 
 extern void	arp_init(void);
 extern int	arp_rcv(struct sk_buff *skb, struct net_device *dev,
-			struct packet_type *pt);
+			struct packet_type *pt, struct net_device *orig_dev);
 extern int	arp_find(unsigned char *haddr, struct sk_buff *skb);
 extern int	arp_ioctl(unsigned int cmd, void __user *arg);
 extern void     arp_send(int type, int ptype, u32 dest_ip,