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/gpio/mpc83xx_spisel_boot.c b/drivers/gpio/mpc83xx_spisel_boot.c
index a35e4de..fd26a36 100644
--- a/drivers/gpio/mpc83xx_spisel_boot.c
+++ b/drivers/gpio/mpc83xx_spisel_boot.c
@@ -78,7 +78,7 @@
 }
 #endif
 
-static int mpc83xx_spisel_boot_platdata_to_priv(struct udevice *dev)
+static int mpc83xx_spisel_boot_plat_to_priv(struct udevice *dev)
 {
 	struct mpc83xx_spisel_boot *priv = dev_get_priv(dev);
 	struct mpc8xxx_gpio_plat *plat = dev_get_plat(dev);
@@ -107,7 +107,7 @@
 	struct mpc83xx_spisel_boot *data = dev_get_priv(dev);
 	char name[32], *str;
 
-	mpc83xx_spisel_boot_platdata_to_priv(dev);
+	mpc83xx_spisel_boot_plat_to_priv(dev);
 
 	snprintf(name, sizeof(name), "MPC@%lx_", data->addr);
 	str = strdup(name);