[NET]: More build fixes for CONFIG_XFRM disabled.

include/net/xfrm.h

@@ -562,6 +562,15 @@ secpath_put(struct sec_path *sp)
 
 extern struct sec_path *secpath_dup(struct sec_path *src);
 
+static inline void
+secpath_reset(struct sk_buff *skb)
+{
+#ifdef CONFIG_XFRM
+	secpath_put(skb->sp);
+	skb->sp = NULL;
+#endif
+}
+
 static inline int
 __xfrm4_state_addr_cmp(struct xfrm_tmpl *tmpl, struct xfrm_state *x)
 {

net/ipv4/ip_gre.c

@@ -601,8 +601,7 @@ int ipgre_rcv(struct sk_buff *skb)
 
 	read_lock(&ipgre_lock);
 	if ((tunnel = ipgre_tunnel_lookup(iph->saddr, iph->daddr, key)) != NULL) {
-		secpath_put(skb->sp);
-		skb->sp = NULL;
+		secpath_reset(skb);
 
 		skb->mac.raw = skb->nh.raw;
 		skb->nh.raw = __pskb_pull(skb, offset);

net/ipv4/ipip.c

@@ -483,8 +483,7 @@ static int ipip_rcv(struct sk_buff *skb)
 			return 0;
 		}
 
-		secpath_put(skb->sp);
-		skb->sp = NULL;
+		secpath_reset(skb);
 
 		skb->mac.raw = skb->nh.raw;
 		skb->nh.raw = skb->data;

net/ipv6/ip6_tunnel.c

@@ -515,8 +515,7 @@ int ip6ip6_rcv(struct sk_buff **pskb, unsigned int *nhoffp)
 			read_unlock(&ip6ip6_lock);
 			goto discard;
 		}
-		secpath_put(skb->sp);
-		skb->sp = NULL;
+		secpath_reset(skb);
 		skb->mac.raw = skb->nh.raw;
 		skb->nh.raw = skb->data;
 		skb->protocol = htons(ETH_P_IPV6);

net/ipv6/sit.c

@@ -377,10 +377,7 @@ static int ipip6_rcv(struct sk_buff *skb)
 
 	read_lock(&ipip6_lock);
 	if ((tunnel = ipip6_tunnel_lookup(iph->saddr, iph->daddr)) != NULL) {
-#ifdef CONFIG_XFRM
-		secpath_put(skb->sp);
-		skb->sp = NULL;
-#endif
+		secpath_reset(skb);
 		skb->mac.raw = skb->nh.raw;
 		skb->nh.raw = skb->data;
 		memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options));