plugin XEP-0060: remove max_items when item_ids is set on getItems

src/plugins/plugin_xep_0060.py

@@ -335,6 +335,8 @@ class XEP_0060(object):
                 - rsm_first, rsm_last, rsm_count, rsm_index: first, last, count and index value of RSMResponse
                 - service, node: service and node used
         """
+        if item_ids and max_items is not None:
+            max_items = None
         if rsm_request and item_ids:
             raise ValueError(u"items_id can't be used with rsm")
         if extra is None: