net: ipv6: Introduce ip6_sk_dst_hoplimit.

This replaces 6 identical code snippets with a call to a new
static inline function.

Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c
index 7b32652..3b0905b 100644
--- a/net/ipv6/icmp.c
+++ b/net/ipv6/icmp.c
@@ -493,12 +493,7 @@
 	if (IS_ERR(dst))
 		goto out;
 
-	if (ipv6_addr_is_multicast(&fl6.daddr))
-		hlimit = np->mcast_hops;
-	else
-		hlimit = np->hop_limit;
-	if (hlimit < 0)
-		hlimit = ip6_dst_hoplimit(dst);
+	hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
 
 	msg.skb = skb;
 	msg.offset = skb_network_offset(skb);
@@ -593,12 +588,7 @@
 	if (IS_ERR(dst))
 		goto out;
 
-	if (ipv6_addr_is_multicast(&fl6.daddr))
-		hlimit = np->mcast_hops;
-	else
-		hlimit = np->hop_limit;
-	if (hlimit < 0)
-		hlimit = ip6_dst_hoplimit(dst);
+	hlimit = ip6_sk_dst_hoplimit(np, &fl6, dst);
 
 	idev = __in6_dev_get(skb->dev);