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/led/led_bcm6358.c b/drivers/led/led_bcm6358.c
index 4bf4a09..3e57cdf 100644
--- a/drivers/led/led_bcm6358.c
+++ b/drivers/led/led_bcm6358.c
@@ -113,7 +113,7 @@
 
 static int bcm6358_led_probe(struct udevice *dev)
 {
-	struct led_uc_plat *uc_plat = dev_get_uclass_platdata(dev);
+	struct led_uc_plat *uc_plat = dev_get_uclass_plat(dev);
 
 	/* Top-level LED node */
 	if (!uc_plat->label) {
@@ -192,7 +192,7 @@
 		if (ret)
 			return ret;
 
-		uc_plat = dev_get_uclass_platdata(dev);
+		uc_plat = dev_get_uclass_plat(dev);
 		uc_plat->label = label;
 	}