videosettings: select VIDEOMENU_43MODE_OPTIONS at runtime

instead of hard coded hardware dependence, select panscan and display
AR options at run time via hw_caps.

src/gui/videosettings.h

@@ -47,6 +47,8 @@ class CVideoSettings : public CMenuWidget, CChangeObserver
 		
 		int width, selected;
 		int showVideoSetup();
+		std::vector<CMenuOptionChooser::keyval_ext> videomenu_43mode_options;
+		void Init43ModeOptions();
 
 public:
 		CVideoSettings(int wizard_mode = SNeutrinoSettings::WIZARD_OFF);