mb/google/rex: Create screebo variant

Create the screebo variant of the rex0 reference board by copying
the template files to a new directory named for the variant.

(Auto-Generated by create_coreboot_variant.sh version 4.5.0).

BUG=b:276814951
BRANCH=None
TEST=util/abuild/abuild -p none -t google/rex -x -a
make sure the build includes GOOGLE_SCREEBO

Change-Id: I8d05ca7c0fe596378ca15d0734d46ad1dc63a1f9
Signed-off-by: Simon Zhou <zhouguohui@huaqin.corp-partner.google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/74391
Reviewed-by: Eric Lai <eric_lai@quanta.corp-partner.google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Kapil Porwal <kapilporwal@google.com>
Reviewed-by: Subrata Banik <subratabanik@google.com>
diff --git a/src/mainboard/google/rex/Kconfig b/src/mainboard/google/rex/Kconfig
index 6cea7fc..62ece95 100644
--- a/src/mainboard/google/rex/Kconfig
+++ b/src/mainboard/google/rex/Kconfig
@@ -80,10 +80,12 @@
 
 config MAINBOARD_PART_NUMBER
 	default "Rex" if BOARD_GOOGLE_REX0
+	default "Screebo" if BOARD_GOOGLE_SCREEBO
 
 config VARIANT_DIR
 	string
 	default "rex0" if BOARD_GOOGLE_REX0
+	default "screebo" if BOARD_GOOGLE_SCREEBO
 
 config DIMM_SPD_SIZE
 	default 512