xfrm: Handle blackhole route creation via afinfo.

That way we don't have to potentially do this in every xfrm_lookup()
caller.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index cf6fdea..053a92e 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -870,7 +870,7 @@
 
 EXPORT_SYMBOL(ip6_route_output);
 
-struct dst_entry *ip6_dst_blackhole(struct net *net, struct dst_entry *dst_orig)
+struct dst_entry *ip6_blackhole_route(struct net *net, struct dst_entry *dst_orig)
 {
 	struct rt6_info *rt = dst_alloc(&ip6_dst_blackhole_ops, 1);
 	struct rt6_info *ort = (struct rt6_info *) dst_orig;
@@ -907,7 +907,6 @@
 	dst_release(dst_orig);
 	return new ? new : ERR_PTR(-ENOMEM);
 }
-EXPORT_SYMBOL_GPL(ip6_dst_blackhole);
 
 /*
  *	Destination cache support functions