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/video/rockchip/rk_vop.c b/drivers/video/rockchip/rk_vop.c
index c20d158..fcb393b 100644
--- a/drivers/video/rockchip/rk_vop.c
+++ b/drivers/video/rockchip/rk_vop.c
@@ -364,7 +364,7 @@
 
 int rk_vop_probe(struct udevice *dev)
 {
-	struct video_uc_platdata *plat = dev_get_uclass_plat(dev);
+	struct video_uc_plat *plat = dev_get_uclass_plat(dev);
 	struct rk_vop_priv *priv = dev_get_priv(dev);
 	int ret = 0;
 	ofnode port, node;
@@ -406,7 +406,7 @@
 
 int rk_vop_bind(struct udevice *dev)
 {
-	struct video_uc_platdata *plat = dev_get_uclass_plat(dev);
+	struct video_uc_plat *plat = dev_get_uclass_plat(dev);
 
 	plat->size = 4 * (CONFIG_VIDEO_ROCKCHIP_MAX_XRES *
 			  CONFIG_VIDEO_ROCKCHIP_MAX_YRES);