xfrm: Const'ify address arguments to ->dst_lookup()

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index 567f08b..18f115a 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -267,8 +267,8 @@
 	struct dst_ops		*dst_ops;
 	void			(*garbage_collect)(struct net *net);
 	struct dst_entry	*(*dst_lookup)(struct net *net, int tos,
-					       xfrm_address_t *saddr,
-					       xfrm_address_t *daddr);
+					       const xfrm_address_t *saddr,
+					       const xfrm_address_t *daddr);
 	int			(*get_saddr)(struct net *net, xfrm_address_t *saddr, xfrm_address_t *daddr);
 	void			(*decode_session)(struct sk_buff *skb,
 						  struct flowi *fl,