hs: Only note a connection attempt with a valid rend_data

For now, prop224 doesn't have a mechanism to note down connection attempts so
we only do it for legacy system using rend_data.

Signed-off-by: David Goulet <dgoulet@torproject.org>

src/or/connection_edge.c

@@ -155,7 +155,9 @@ connection_mark_unattached_ap_,(entry_connection_t *conn, int endreason,
    * but we should fix it someday anyway. */
   if ((edge_conn->on_circuit != NULL || edge_conn->edge_has_sent_end) &&
       connection_edge_is_rendezvous_stream(edge_conn)) {
-    rend_client_note_connection_attempt_ended(edge_conn->rend_data);
+    if (edge_conn->rend_data) {
+      rend_client_note_connection_attempt_ended(edge_conn->rend_data);
+    }
   }
 
   if (base_conn->marked_for_close) {