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/sh_mmcif.c b/drivers/mmc/sh_mmcif.c
index f3d10ac..723e3e3 100644
--- a/drivers/mmc/sh_mmcif.c
+++ b/drivers/mmc/sh_mmcif.c
@@ -744,7 +744,7 @@
 	.bind			= sh_mmcif_dm_bind,
 	.probe			= sh_mmcif_dm_probe,
 	.priv_auto	= sizeof(struct sh_mmcif_host),
-	.platdata_auto	= sizeof(struct sh_mmcif_plat),
+	.plat_auto	= sizeof(struct sh_mmcif_plat),
 	.ops			= &sh_mmcif_dm_ops,
 };
 #endif