hisi_sas: Use u64 for qw0 in free_device_v1_hw()

By reading in itct.qw0 into a 32b variable the top 32 bits were being
lost.  In practice this was OK as they were zeroes.

Fixes: 27a3f229 ("hisi_sas: Add cq interrupt")

Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Shane Seymour <shane.seymour@hpe.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>