scsi: drop reason argument from ->change_queue_depth

Drop the now unused reason argument from the ->change_queue_depth method.
Also add a return value to scsi_adjust_queue_depth, and rename it to
scsi_change_queue_depth now that it can be used as the default
->change_queue_depth implementation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Reviewed-by: Hannes Reinecke <hare@suse.de>
diff --git a/drivers/scsi/ips.c b/drivers/scsi/ips.c
index 454741a..e5c2843 100644
--- a/drivers/scsi/ips.c
+++ b/drivers/scsi/ips.c
@@ -1210,7 +1210,7 @@
 		min = ha->max_cmds / 2;
 		if (ha->enq->ucLogDriveCount <= 2)
 			min = ha->max_cmds - 1;
-		scsi_adjust_queue_depth(SDptr, min);
+		scsi_change_queue_depth(SDptr, min);
 	}
 
 	SDptr->skip_ms_page_8 = 1;