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/misc/i2c_eeprom_emul.c b/drivers/misc/i2c_eeprom_emul.c
index 2089df1..65db9c8 100644
--- a/drivers/misc/i2c_eeprom_emul.c
+++ b/drivers/misc/i2c_eeprom_emul.c
@@ -201,6 +201,6 @@
 	.probe		= sandbox_i2c_eeprom_probe,
 	.remove		= sandbox_i2c_eeprom_remove,
 	.priv_auto	= sizeof(struct sandbox_i2c_flash),
-	.platdata_auto	= sizeof(struct sandbox_i2c_flash_plat_data),
+	.plat_auto	= sizeof(struct sandbox_i2c_flash_plat_data),
 	.ops		= &sandbox_i2c_emul_ops,
 };