scsi: hisi_sas: Delete some unused callbacks

mainline inclusion
from mainline-master
commit 2843d2fb
category: bugfix
bugzilla: 175270
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=2843d2fb42254ac443c83e5e0b97e1cae6b7a4de

------------------------------------------------------------------------

The debugfs code has been relocated to v3 hw driver, so delete unused
struct hisi_sas_hw function pointers snapshot_{prepare, restore}.

Link: https://lore.kernel.org/r/1617709711-195853-2-git-send-email-john.garry@huawei.comSigned-off-by: NLuo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NOuyangdelong <ouyangdelong@huawei.com>
Signed-off-by: NNifujia <nifujia1@hisilicon.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

drivers/scsi/hisi_sas/hisi_sas.h

@@ -346,8 +346,6 @@ struct hisi_sas_hw {
 				u8 reg_index, u8 reg_count, u8 *write_data);
 	void (*wait_cmds_complete_timeout)(struct hisi_hba *hisi_hba,
 					   int delay_ms, int timeout_ms);
-	void (*snapshot_prepare)(struct hisi_hba *hisi_hba);
-	void (*snapshot_restore)(struct hisi_hba *hisi_hba);
 	int complete_hdr_size;
 	struct scsi_host_template *sht;
 };