[libata] libata-scsi.c: Add function parameter documentation

Add the documentation of parameters of ata_change_queue_depth to silence the warning of make xmldocs

Signed-off-by: Marcos paulo de Souza <marcos.mage@gmail.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 72a9770..2a5412e 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -1217,6 +1217,10 @@
 
 /**
  *	__ata_change_queue_depth - helper for ata_scsi_change_queue_depth
+ *	@ap: ATA port to which the device change the queue depth
+ *	@sdev: SCSI device to configure queue depth for
+ *	@queue_depth: new queue depth
+ *	@reason: calling context
  *
  *	libsas and libata have different approaches for associating a sdev to
  *	its ata_port.