[zebra] linux policy routing support with ipv6

Quagga support linux policy routing (ip route ... table $X) with zebra.conf
table $X option.  It works fine on ipv4.  On ipv6 the parameter is ignored
(table 0 is used).

* zebra/...: Pass appropriate table arg to rib_{add,delete}_ipv6
diff --git a/zebra/zserv.c b/zebra/zserv.c
index 05380d6..a566e6d 100644
--- a/zebra/zserv.c
+++ b/zebra/zserv.c
@@ -964,10 +964,10 @@
     api.metric = 0;
     
   if (IN6_IS_ADDR_UNSPECIFIED (&nexthop))
-    rib_add_ipv6 (api.type, api.flags, &p, NULL, ifindex, 0, api.metric,
+    rib_add_ipv6 (api.type, api.flags, &p, NULL, ifindex, zebrad.rtm_table_default, api.metric,
 		  api.distance);
   else
-    rib_add_ipv6 (api.type, api.flags, &p, &nexthop, ifindex, 0, api.metric,
+    rib_add_ipv6 (api.type, api.flags, &p, &nexthop, ifindex, zebrad.rtm_table_default, api.metric,
 		  api.distance);
   return 0;
 }
@@ -1030,9 +1030,9 @@
     api.metric = 0;
     
   if (IN6_IS_ADDR_UNSPECIFIED (&nexthop))
-    rib_delete_ipv6 (api.type, api.flags, &p, NULL, ifindex, 0);
+    rib_delete_ipv6 (api.type, api.flags, &p, NULL, ifindex, client->rtm_table);
   else
-    rib_delete_ipv6 (api.type, api.flags, &p, &nexthop, ifindex, 0);
+    rib_delete_ipv6 (api.type, api.flags, &p, &nexthop, ifindex, client->rtm_table);
   return 0;
 }