Rotating steering wheel in onroad UI

Added toggle to rotate the steering wheel in the top right corner of the onroad UI.

selfdrive/ui/qt/onroad.h

@@ -77,6 +77,8 @@ private:
   // FrogPilot variables
   UIScene &scene;
 
+  bool rotatingWheel;
+  int steeringAngleDeg;
   int y_offset;
 };