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/video/mali_dp.c b/drivers/video/mali_dp.c
index 0ffdd7b..6c73bd2 100644
--- a/drivers/video/mali_dp.c
+++ b/drivers/video/mali_dp.c
@@ -260,7 +260,7 @@
 static int malidp_probe(struct udevice *dev)
 {
 	struct video_priv *uc_priv = dev_get_uclass_priv(dev);
-	struct video_uc_platdata *uc_plat = dev_get_uclass_platdata(dev);
+	struct video_uc_platdata *uc_plat = dev_get_uclass_plat(dev);
 	ofnode framebuffer = ofnode_find_subnode(dev_ofnode(dev), "framebuffer");
 	struct malidp_priv *priv = dev_get_priv(dev);
 	struct display_timing timings;
@@ -382,7 +382,7 @@
 
 static int malidp_bind(struct udevice *dev)
 {
-	struct video_uc_platdata *uc_plat = dev_get_uclass_platdata(dev);
+	struct video_uc_platdata *uc_plat = dev_get_uclass_plat(dev);
 
 	/* choose max possible size: 2K x 2K, XRGB888 framebuffer */
 	uc_plat->size = 4 * 2048 * 2048;