[IPv6] route: Simplify ip6_del_rt()

Provide a simple ip6_del_rt() for the majority of users and
an alternative for the exception via netlink. Avoids code
obfuscation.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/ip6_route.h b/include/net/ip6_route.h
index 01bfe40..a7e6086 100644
--- a/include/net/ip6_route.h
+++ b/include/net/ip6_route.h
@@ -69,10 +69,7 @@
 					   struct nlmsghdr *,
 					   void *rtattr,
 					   struct netlink_skb_parms *req);
-extern int			ip6_del_rt(struct rt6_info *,
-					   struct nlmsghdr *,
-					   void *rtattr,
-					   struct netlink_skb_parms *req);
+extern int			ip6_del_rt(struct rt6_info *);
 
 extern int			ip6_rt_addr_add(struct in6_addr *addr,
 						struct net_device *dev,