Doc: clarify ownership after QStackedWidget::removeWidget

Change-Id: Ia14b72cdac3205a3896c47ecc81b31adb508181b
Task-number: QTBUG-44891
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@theqtcompany.com>

src/widgets/widgets/qstackedwidget.cpp

@@ -182,7 +182,9 @@ int QStackedWidget::insertWidget(int index, QWidget *widget)
     not deleted but simply removed from the stacked layout, causing it
     to be hidden.
 
-    \b{Note:} Ownership of \a widget reverts to the application.
+    \note Parent object and parent widget of \a widget will remain the
+    QStackedWidget. If the application wants to reuse the removed
+    \a widget, then it is recommended to re-parent it.
 
     \sa addWidget(), insertWidget(), currentWidget()
 */