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/ncr53c8xx.c b/drivers/scsi/ncr53c8xx.c
index 9c331b7b..5b93ed8 100644
--- a/drivers/scsi/ncr53c8xx.c
+++ b/drivers/scsi/ncr53c8xx.c
@@ -7997,7 +7997,7 @@
 	if (depth_to_use > MAX_TAGS)
 		depth_to_use = MAX_TAGS;
 
-	scsi_adjust_queue_depth(device, depth_to_use);
+	scsi_change_queue_depth(device, depth_to_use);
 
 	/*
 	**	Since the queue depth is not tunable under Linux,