ClangTools: Fix a bugprone-parent-virtual-call

clangtoolsdiagnosticview.cpp:286:16: warning: qualified name
'QObject::eventFilter' refers to a member overridden in subclass; did
you mean 'QAbstractItemView'?

Change-Id: Ifcff716b336324384d0164925b548f61cf460449
Reviewed-by: Cristian Adam <cristian.adam@qt.io>
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@qt.io>

src/plugins/clangtools/clangtoolsdiagnosticview.cpp

@@ -283,7 +283,7 @@ bool DiagnosticView::eventFilter(QObject *watched, QEvent *event)
         return true;
     }
     default:
-        return QObject::eventFilter(watched, event);
+        return QAbstractItemView::eventFilter(watched, event);
     }
 }