Gui: refactor buttons remapping (#1949)

* Gui: refactor buttons remapping
  Instead of calling 3 separate functions with a ton of switch/case statements,
  use a 2-dimensional lookup table to remap buttons based on the orientation.
* Gui: cleanup input mapping and fix incorrect asserts
* SnakeGame: handle input special case

Co-authored-by: Aleksandr Kutuzov <alleteam@gmail.com>

applications/services/gui/view_port.h

@@ -19,6 +19,7 @@ typedef enum {
     ViewPortOrientationHorizontalFlip,
     ViewPortOrientationVertical,
     ViewPortOrientationVerticalFlip,
+    ViewPortOrientationMAX, /**< Special value, don't use it */
 } ViewPortOrientation;
 
 /** ViewPort Draw callback