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/intel_broadwell_gpio.c b/drivers/gpio/intel_broadwell_gpio.c
index cb21740..b05233f 100644
--- a/drivers/gpio/intel_broadwell_gpio.c
+++ b/drivers/gpio/intel_broadwell_gpio.c
@@ -185,5 +185,5 @@
 	.ofdata_to_platdata	= broadwell_gpio_ofdata_to_platdata,
 	.probe	= broadwell_gpio_probe,
 	.priv_auto	= sizeof(struct broadwell_bank_priv),
-	.platdata_auto	= sizeof(struct broadwell_bank_platdata),
+	.plat_auto	= sizeof(struct broadwell_bank_platdata),
 };