scsi: libsas: fix memory leak in sas_smp_get_phy_events()

We've got a memory leak with the following producer:

while true;
do cat /sys/class/sas_phy/phy-1:0:12/invalid_dword_count >/dev/null;
done

The buffer req is allocated and not freed after we return. Fix it.

Fixes: 2908d778ab3e ("[SCSI] aic94xx: new driver")
Signed-off-by: Jason Yan <yanaijie@huawei.com>
CC: John Garry <john.garry@huawei.com>
CC: chenqilin <chenqilin2@huawei.com>
CC: chenxiang <chenxiang66@hisilicon.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
static int sas_configure_phy(struct domain_device *dev, int phy_id,
				    u8 *sas_addr, int include)
{
	int index;
	int present;
	int res;

	res = sas_configure_present(dev, phy_id, sas_addr, &index, &present);
	if (res)
		return res;
	if (include ^ present)
		return sas_configure_set(dev, phy_id, sas_addr, index,include);

	return res;
}

static int sas_configure_phy(struct domain_device *dev, int phy_id,
				    u8 *sas_addr, int include)
{
	int index;
	int present;
	int res;

	res = sas_configure_present(dev, phy_id, sas_addr, &index, &present);
	if (res)
		return res;
	if (include ^ present)
		return sas_configure_set(dev, phy_id, sas_addr, index,include);

	return res;
}
