net: reduce structures when XFRM=n

ifdef out
* struct sk_buff::sp		(pointer)
* struct dst_entry::xfrm	(pointer)
* struct sock::sk_policy	(2 pointers)

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index c77db0b..7d92fd9 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -490,7 +490,7 @@
 	   We don't send redirects to frames decapsulated from IPsec.
 	 */
 	if (skb->dev == dst->dev && dst->neighbour && opt->srcrt == 0 &&
-	    !skb->sp) {
+	    !skb_sec_path(skb)) {
 		struct in6_addr *target = NULL;
 		struct rt6_info *rt;
 		struct neighbour *n = dst->neighbour;