scsi: hisi_sas: Snapshot AXI and RAS register at debugfs

The AXI and RAS register values should also should be snapshot at debugfs.

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