remove makefile include, and fix link error
Makefile: comment CFLAGS += -I $(PWD)/CORTEX_M4F_STM32F407ZG-SK/game
game.c: revert 'demoMode' modifier 'static' ;
game.h: add header file <inttypes.h>
game.h: extern uint8_t demoMode
main.c: #include "game.h" -> #include "game/game.h"
main.c: remove extern uint8_t demoMode;