BACKENDS: Drop native game joystick support in replacement for emulated from core events backend.

engines/engine.h

@@ -206,14 +206,7 @@ public:
 		 * The engine will need to read the actual resolution used by the
 		 * backend using OSystem::getWidth and OSystem::getHeight.
 		 */
-		kSupportsArbitraryResolutions, // ResidualVM specific
-
-		/**
-		 * Engine must receive joystick events because the game uses them.
-		 * For engines which have not this feature, joystick events are converted
-		 * to mouse events.
-		 */
-		kSupportsJoystick // ResidualVM specific
+		kSupportsArbitraryResolutions // ResidualVM specific
 	};