[IPV6]: Make ndisc_dst_alloc() common for later use.

For later use, this patch is renaming ndisc_dst_alloc()
(and related function/structures) to icmp6_dst_alloc()
(and so on).  This patch also removing unused function-
pointer argument for it.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
diff --git a/include/net/ip6_route.h b/include/net/ip6_route.h
index f99e4f0..8d155a6 100644
--- a/include/net/ip6_route.h
+++ b/include/net/ip6_route.h
@@ -73,11 +73,11 @@
 					    struct in6_addr *saddr,
 					    int oif, int flags);
 
-extern struct dst_entry *ndisc_dst_alloc(struct net_device *dev,
+extern struct dst_entry *icmp6_dst_alloc(struct net_device *dev,
 					 struct neighbour *neigh,
-					 struct in6_addr *addr,
-					 int (*output)(struct sk_buff *));
-extern int ndisc_dst_gc(int *more);
+					 struct in6_addr *addr);
+extern int icmp6_dst_gc(int *more);
+
 extern void fib6_force_start_gc(void);
 
 extern struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,