make recovery device support an optional feature

src/welcomewidget.cpp

@@ -90,8 +90,11 @@ void WelcomeWidget::setupUI()
 
     m_mainLayout->addWidget(m_githubLabel, 0, Qt::AlignCenter);
 
+    // FIXME: we need to disable specific deps in diagnosewidget
+    // not the whole widget when EnableRecoveryDeviceSupport is off
     // no additional deps needed on macOS
-#ifndef __APPLE__
+#if !defined(__APPLE__) && defined(ENABLE_RECOVERY_DEVICE_SUPPORT)
+
     DiagnoseWidget *diagnoseWidget = new DiagnoseWidget();
     m_mainLayout->addWidget(diagnoseWidget);
 #endif