Fix compile with optional components disabled

src/widgets/osd_x11.cpp

@@ -157,6 +157,10 @@ void OSD::ShowMessageNative(const QString &summary, const QString &message, cons
   QDBusPendingCallWatcher *watcher = new QDBusPendingCallWatcher(reply, this);
   connect(watcher, SIGNAL(finished(QDBusPendingCallWatcher*)), SLOT(CallFinished(QDBusPendingCallWatcher*)));
 #else   // HAVE_DBUS
+  Q_UNUSED(summary)
+  Q_UNUSED(message)
+  Q_UNUSED(icon)
+  Q_UNUSED(image)
   qLog(Warning) << "not implemented";
 #endif  // HAVE_DBUS
 
@@ -179,5 +183,6 @@ void OSD::CallFinished(QDBusPendingCallWatcher *watcher) {
     last_notification_time_ = QDateTime::currentDateTime();
   }
 }
+#else
+void OSD::CallFinished() {}
 #endif
-