scsi: hisi_sas: Relocate DMA unmap of SMP task

Currently SMP tasks are DMA unmapped only when cq of SMP I/O is returned
normally. If the cq of SMP I/O is returned with exception actually SMP TAS
is never unmapped. Relocate DMA unmap of SMP task to fix the issue.

Link: https://lore.kernel.org/r/1657823002-139010-4-git-send-email-john.garry@huawei.com


Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>