tty: implement read/write support

kernel/tty/driver.c

@@ -8,7 +8,7 @@ static struct vm_cache tty_driver_cache = {
 static struct queue tty_drivers;
 static spin_lock_t tty_drivers_lock;
 
-kern_status_t tty_init(void)
+kern_status_t tty_bootstrap(void)
 {
 	vm_cache_init(&tty_driver_cache);
 	tty_drivers = QUEUE_INIT;