dev: introduce skb_scrub_packet()

The goal of this new function is to perform all needed cleanup before sending
an skb into another netns.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index a7393ad..6b06023 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -2384,6 +2384,7 @@
 				 struct sk_buff *skb1, const u32 len);
 extern int	       skb_shift(struct sk_buff *tgt, struct sk_buff *skb,
 				 int shiftlen);
+extern void	       skb_scrub_packet(struct sk_buff *skb);
 
 extern struct sk_buff *skb_segment(struct sk_buff *skb,
 				   netdev_features_t features);