Improve CMake files (#460)

src/widgets/osd.h

@@ -98,9 +98,8 @@ class OSD : public QObject {
  private slots:
 #ifdef HAVE_DBUS
   void CallFinished(QDBusPendingCallWatcher *watcher);
-#else
-  void CallFinished();
 #endif
+  void CallFinished();
   void AlbumCoverLoaded(const Song &song, const QUrl &cover_url, const QImage &image);
 
  private:

src/widgets/osd_x11.cpp

@@ -184,6 +184,6 @@ void OSD::CallFinished(QDBusPendingCallWatcher *watcher) {
     last_notification_time_ = QDateTime::currentDateTime();
   }
 }
-#else
-void OSD::CallFinished() {}
 #endif
+void OSD::CallFinished() {}
+