Bug requesting non-existent data with private_get command (#1690)

src/mod_admin_extra.erl

@@ -1363,7 +1363,7 @@ get_last(User, Server) ->
 %% <aa xmlns='bb'>Cluth</aa>
 
 private_get(Username, Host, Element, Ns) ->
-    ElementXml = [{Ns, #xmlel{name = Element, attrs = [{<<"xmlns">>, Ns}]}}],
+    ElementXml = #xmlel{name = Element, attrs = [{<<"xmlns">>, Ns}]},
     Els = mod_private:get_data(jid:nodeprep(Username), jid:nameprep(Host),
 			       [{Ns, ElementXml}]),
     binary_to_list(fxml:element_to_binary(xmpp:encode(#private{xml_els = Els}))).