scsi: sd: Use separate buf for START_STOP in sd_spinup_disk()

We currently reuse the cmd buffer for the TUR and START_STOP commands
which requires us to reset the buffer when retrying. This has us use
separate buffers for the 2 commands so we can make them const and I think
it makes it easier to handle for retries but does not add too much extra to
the stack use.
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Link: https://lore.kernel.org/r/20240123002220.129141-5-michael.christie@oracle.comReviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Martin Wilck <mwilck@suse.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/sd.c

@@ -2318,14 +2318,16 @@ sd_spinup_disk(struct scsi_disk *sdkp)
 			 * Issue command to spin up drive when not ready
 			 */
 			if (!spintime) {
+				/* Return immediately and start spin cycle */
+				const u8 start_cmd[10] = {
+					[0] = START_STOP,
+					[1] = 1,
+					[4] = sdkp->device->start_stop_pwr_cond ?
+						0x11 : 1,
+				};
+
 				sd_printk(KERN_NOTICE, sdkp, "Spinning up disk...");
-				cmd[0] = START_STOP;
-				cmd[1] = 1;	/* Return immediately */
-				memset((void *) &cmd[2], 0, 8);
-				cmd[4] = 1;	/* Start spin cycle */
-				if (sdkp->device->start_stop_pwr_cond)
-					cmd[4] |= 1 << 4;
-				scsi_execute_cmd(sdkp->device, cmd,
+				scsi_execute_cmd(sdkp->device, start_cmd,
 						 REQ_OP_DRV_IN, NULL, 0,
 						 SD_TIMEOUT, sdkp->max_retries,
 						 &exec_args);