xfrm: use secpath_exist where applicable

Will reduce noise when skb->sp is removed later in this series.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index af72344..31220ed 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -1185,7 +1185,7 @@ static inline int __xfrm_policy_check2(struct sock *sk, int dir,
 	if (sk && sk->sk_policy[XFRM_POLICY_IN])
 		return __xfrm_policy_check(sk, ndir, skb, family);
 
-	return	(!net->xfrm.policy_count[dir] && !skb->sp) ||
+	return	(!net->xfrm.policy_count[dir] && !secpath_exists(skb)) ||
 		(skb_dst(skb)->flags & DST_NOPOLICY) ||
 		__xfrm_policy_check(sk, ndir, skb, family);
 }