dm: treewide: Rename 'platdata' variables to just 'plat'

We use 'priv' for private data but often use 'platdata' for platform data.
We can't really use 'pdata' since that is ambiguous (it could mean private
or platform data).

Rename some of the latter variables to end with 'plat' for consistency.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/ata/sata_sil.c b/drivers/ata/sata_sil.c
index 4d83f75..2bc3d22 100644
--- a/drivers/ata/sata_sil.c
+++ b/drivers/ata/sata_sil.c
@@ -708,7 +708,7 @@
 #else
 static int scan_sata(struct udevice *blk_dev, int dev)
 {
-	struct blk_desc *desc = dev_get_uclass_platdata(blk_dev);
+	struct blk_desc *desc = dev_get_uclass_plat(blk_dev);
 	struct sil_sata_priv *priv = dev_get_platdata(blk_dev);
 	struct sil_sata *sata = priv->sil_sata_desc[dev];
 #endif
@@ -772,7 +772,7 @@
 	.name = "sata_sil_blk",
 	.id = UCLASS_BLK,
 	.ops = &sata_sil_blk_ops,
-	.platdata_auto	= sizeof(struct sil_sata_priv),
+	.plat_auto	= sizeof(struct sil_sata_priv),
 };
 
 static int sil_unbind_device(struct udevice *dev)