CppTools: Use Qt5-style connects

Mostly done by clazy.

Change-Id: I0fbbbe1a2d28b79bcb83093d608bca6e2f927ebb
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@qt.io>

src/plugins/cpptools/semantichighlighter.h

@@ -70,11 +70,10 @@ public:
 
     void run();
 
-private slots:
+private:
     void onHighlighterResultAvailable(int from, int to);
     void onHighlighterFinished();
 
-private:
     void connectWatcher();
     void disconnectWatcher();