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/gpio/sunxi_gpio.c b/drivers/gpio/sunxi_gpio.c
index dea71a7..62d584a 100644
--- a/drivers/gpio/sunxi_gpio.c
+++ b/drivers/gpio/sunxi_gpio.c
@@ -285,7 +285,7 @@
 {
 	struct sunxi_gpio_soc_data *soc_data =
 		(struct sunxi_gpio_soc_data *)dev_get_driver_data(parent);
-	struct sunxi_gpio_platdata *plat = parent->platdata;
+	struct sunxi_gpio_platdata *plat = parent->plat;
 	struct sunxi_gpio_reg *ctlr;
 	int bank, ret;