Don't send wildcard requests to new nodes.

This avoids a network meltdown in extreme cases.
Thanks to Teco Boot.

(cherry picked from commit a4fd38d4)

neighbour.c

@@ -191,12 +191,6 @@ update_neighbour(struct neighbour *neigh, int hello, int hello_interval)
         }
     }
 
-    if((neigh->reach & 0xFC00) == 0xC000) {
-        /* This is a newish neighbour, let's request a full route dump.
-           We ought to avoid this when the network is dense */
-        send_unicast_request(neigh, NULL, 0, NULL, 0);
-        send_ihu(neigh, NULL);
-    }
     return rc;
 }