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/net/eepro100.c b/drivers/net/eepro100.c
index 59582b9..f47caf1 100644
--- a/drivers/net/eepro100.c
+++ b/drivers/net/eepro100.c
@@ -1010,7 +1010,7 @@
 	.probe	= eepro100_probe,
 	.ops	= &eepro100_ops,
 	.priv_auto	= sizeof(struct eepro100_priv),
-	.platdata_auto	= sizeof(struct eth_pdata),
+	.plat_auto	= sizeof(struct eth_pdata),
 };
 
 U_BOOT_PCI_DEVICE(eth_eepro100, supported);