scsi: hisi_sas: Warn in v3 hw channel interrupt handler when status reg cleared

If a channel interrupt occurs without any status bit set, the handler will
return directly. However, if such redundant interrupts are received, it's
better to check what happen, so add logs for this.

Link: https://lore.kernel.org/r/1617709711-195853-6-git-send-email-john.garry@huawei.com


Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: Yihang Li <liyihang6@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>