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/mmc/stm32_sdmmc2.c b/drivers/mmc/stm32_sdmmc2.c
index 80eecb6..df5bb78 100644
--- a/drivers/mmc/stm32_sdmmc2.c
+++ b/drivers/mmc/stm32_sdmmc2.c
@@ -718,5 +718,5 @@
 	.probe = stm32_sdmmc2_probe,
 	.bind = stm32_sdmmc_bind,
 	.priv_auto	= sizeof(struct stm32_sdmmc2_priv),
-	.platdata_auto	= sizeof(struct stm32_sdmmc2_plat),
+	.plat_auto	= sizeof(struct stm32_sdmmc2_plat),
 };