Remove game.door_left/right/up/down variables

These don't do anything, and in fact are actively harmful by disabling
room transitions if your roomx/roomy is glitched.

desktop_version/src/Game.h

@@ -211,10 +211,6 @@ public:
     const char* saveFilePath;
 
 
-    int door_left;
-    int door_right;
-    int door_up;
-    int door_down;
     int roomx, roomy;
     int prevroomx, prevroomy;