UI: hide power off button on C3 while onroad (#23689)

* Grey out power button while onroad - comma three only

* Apply suggestions from code review

Co-authored-by: Adeeb Shihadeh <adeebshihadeh@gmail.com>

selfdrive/ui/qt/offroad/settings.cc

@@ -158,6 +158,10 @@ DevicePanel::DevicePanel(SettingsWindow *parent) : ListWidget(parent) {
   power_layout->addWidget(poweroff_btn);
   QObject::connect(poweroff_btn, &QPushButton::clicked, this, &DevicePanel::poweroff);
 
+  if (Hardware::TICI()) {
+    connect(uiState(), &UIState::offroadTransition, poweroff_btn, &QPushButton::setVisible);
+  }
+
   setStyleSheet(R"(
     #reboot_btn { height: 120px; border-radius: 15px; background-color: #393939; }
     #reboot_btn:pressed { background-color: #4a4a4a; }