ipv6: Initialize the neighbour pointer of rt6_info on allocation

git commit 97cac082 (ipv6: Store route neighbour in rt6_info struct)
added a neighbour pointer to rt6_info. Currently we don't initialize
this pointer at allocation time. We assume this pointer to be valid
if it is not a null pointer, so initialize it on allocation.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv6/route.c

@@ -273,7 +273,7 @@ static inline struct rt6_info *ip6_dst_alloc(struct net *net,
 					0, 0, flags);
 
 	if (rt) {
-		memset(&rt->rt6i_table, 0,
+		memset(&rt->n, 0,
 		       sizeof(*rt) - sizeof(struct dst_entry));
 		rt6_init_peer(rt, table ? &table->tb6_peers : net->ipv6.peers);
 	}