Set dockAction enabled according to settings

Panels are unlocked even they're set locked in settings at start of the app.
This sets panels locked according to the setting.

BUG:478117

src/dolphindockwidget.cpp

@@ -64,7 +64,7 @@ void DolphinDockWidget::setLocked(bool lock)
                 m_dockTitleBar = new DolphinDockTitleBar(this);
             }
             setTitleBarWidget(m_dockTitleBar);
-            setFeatures(QDockWidget::NoDockWidgetFeatures);
+            setFeatures(QDockWidget::DockWidgetClosable);
         } else {
             setTitleBarWidget(nullptr);
             setFeatures(DefaultDockWidgetFeatures);