net: reset skb queue mapping when rx'ing over tunnel

Reset queue mapping when an skb is reentering the stack via a tunnel.
On second pass, the queue mapping from the original device is no
longer valid.

Signed-off-by: Tom Herbert <[e-mail]>
Acked-by: Eric Dumazet <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

include/net/dst.h

···
 	dev->stats.rx_packets++;
 	dev->stats.rx_bytes += skb->len;
 	skb->rxhash = 0;
+	skb_set_queue_mapping(skb, 0);
 	skb_dst_drop(skb);
 	nf_reset(skb);
 }