scsi: ch: Remove unit_attention

unit_attention is not used so remove it.
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Link: https://lore.kernel.org/r/20240123002220.129141-11-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/ch.c

@@ -113,7 +113,6 @@ typedef struct {
 	struct scsi_device  **dt;        /* ptrs to data transfer elements */
 	u_int               firsts[CH_TYPES];
 	u_int               counts[CH_TYPES];
-	u_int               unit_attention;
 	u_int		    voltags;
 	struct mutex	    lock;
 } scsi_changer;
@@ -208,7 +207,6 @@ ch_do_scsi(scsi_changer *ch, unsigned char *cmd, int cmd_len,
 
 		switch(sshdr.sense_key) {
 		case UNIT_ATTENTION:
-			ch->unit_attention = 1;
 			if (retries++ < 3)
 				goto retry;
 			break;