dm: treewide: Rename ..._platdata variables to just ..._plat

Try to maintain some consistency between these variables by using _plat as
a suffix for them.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/scsi/scsi-uclass.c b/drivers/scsi/scsi-uclass.c
index e9970a7..90a0add 100644
--- a/drivers/scsi/scsi-uclass.c
+++ b/drivers/scsi/scsi-uclass.c
@@ -35,5 +35,5 @@
 UCLASS_DRIVER(scsi) = {
 	.id		= UCLASS_SCSI,
 	.name		= "scsi",
-	.per_device_plat_auto	= sizeof(struct scsi_platdata),
+	.per_device_plat_auto	= sizeof(struct scsi_plat),
 };