dm: treewide: Rename ..._platdata variables to just ..._plat

Try to maintain some consistency between these variables by using _plat as
a suffix for them.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/lib/smbios.c b/lib/smbios.c
index 4bd1655..1e10fa8 100644
--- a/lib/smbios.c
+++ b/lib/smbios.c
@@ -229,7 +229,7 @@
 
 	uclass_find_first_device(UCLASS_CPU, &cpu);
 	if (cpu) {
-		struct cpu_platdata *plat = dev_get_parent_plat(cpu);
+		struct cpu_plat *plat = dev_get_parent_plat(cpu);
 
 		if (plat->family)
 			processor_family = plat->family;