* lib/prefix.[hc]: inet6_ntoa utility function copied from
	  ripngd/ripngd.c (inet6_ntop).
	* ripngd.[hc]: Remove inet6_ntop() and any usage of it. inet6_ntoa()
	  from lib is used now.
	* ripng_interface.c: inet6_ntop() -> inet6_ntoa().
	* ripng_peer.c: inet6_ntop() -> inet6_ntoa().
diff --git a/lib/prefix.c b/lib/prefix.c
index 8207544..56539fc 100644
--- a/lib/prefix.c
+++ b/lib/prefix.c
@@ -735,3 +735,14 @@
   return 1;
 }
 
+#ifdef HAVE_IPV6
+/* Utility function for making IPv6 address string. */
+const char *
+inet6_ntoa (struct in6_addr *addr)
+{
+  static char buf[INET6_ADDRSTRLEN];
+
+  inet_ntop (AF_INET6, addr, buf, INET6_ADDRSTRLEN);
+  return buf;
+}
+#endif /* HAVE_IPV6 */