fix: check if all threads is stopped before destroye data

struct.h

@@ -28,6 +28,8 @@ typedef struct s_philo
 	size_t			last_eat;
 	pthread_mutex_t	last_sleep_mutex;
 	size_t			last_sleep;
+	pthread_mutex_t	stop_mutex;
+	bool			stop;
 	t_data			*data;
 }	t_philo;