util/mb/google: Add support for rex

Add the file templates for creating a new variant of Rex.

Signed-off-by: Subrata Banik <subratabanik@google.com>
Change-Id: I4abca1f999accc008eb2549fcc13199b8d9bdc7a
Reviewed-on: https://review.coreboot.org/c/coreboot/+/71086
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Kapil Porwal <kapilporwal@google.com>

util/mainboard/google/rex0/template/overridetree.cb

@@ -0,0 +1,6 @@
+chip soc/intel/meteorlake
+
+        device domain 0 on
+        end
+
+end