ata: libahci: replace obsolete simple_strtoul() with kstrtouint()

static ssize_t ahci_led_store(struct ata_port *ap, const char *buf,

				size_t size)

{

	int state;

	unsigned int state;

	int pmp;

	struct ahci_port_priv *pp = ap->private_data;

	struct ahci_em_priv *emp;

	state = simple_strtoul(buf, NULL, 0);

	if (kstrtouint(buf, 0, &state) < 0)

		return -EINVAL;

	/* get the slot number from the message */

	pmp = (state & EM_MSG_LED_PMP_SLOT) >> 8;