Remove duplicate UIA error display

resources/qml/Root.qml

@@ -347,11 +347,6 @@ Pane {
             return UIA.submit3pidToken(t);
         }
     }
-    Platform.MessageDialog {
-        id: uiaErrorDialog
-
-        buttons: Platform.MessageDialog.Ok
-    }
     Platform.MessageDialog {
         id: uiaConfirmationLinkDialog
 
@@ -368,10 +363,6 @@ Pane {
         function onEmail() {
             uiaEmailPrompt.show();
         }
-        function onError(msg) {
-            uiaErrorDialog.text = msg;
-            uiaErrorDialog.open();
-        }
         function onPassword() {
             console.log("UIA: password needed");
             uiaPassPrompt.show();