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/i2c/Kconfig b/drivers/i2c/Kconfig
index 3795808..403602f 100644
--- a/drivers/i2c/Kconfig
+++ b/drivers/i2c/Kconfig
@@ -11,7 +11,7 @@
 	  Enable driver model for I2C. The I2C uclass interface: probe, read,
 	  write and speed, is implemented with the bus drivers operations,
 	  which provide methods for bus setting and data transfer. Each chip
-	  device (bus child) info is kept as parent platdata. The interface
+	  device (bus child) info is kept as parent plat. The interface
 	  is defined in include/i2c.h.
 
 config I2C_CROS_EC_TUNNEL