CtfVisualizer: Destroy CtfTool earlier again

Amends 796053d7.

After all, the defaulted destructor of the class did some actual work
via the destructors of the QScopedPointer members.

Change-Id: If6dc8a3d57961ec263fced11f9fa9f7e9f8c54cc
Reviewed-by: Jarek Kobus <jaroslaw.kobus@qt.io>

src/plugins/ctfvisualizer/ctfvisualizerplugin.cpp

@@ -14,7 +14,7 @@ class CtfVisualizerPlugin : public ExtensionSystem::IPlugin
 
     void initialize() final
     {
-        setupCtfVisualizerTool();
+        setupCtfVisualizerTool(this);
     }
 };