mb/google/brya: Create redrix variant

mb/google/brya: Create redrix variant

Create the redrix variant of the brya0 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:192052098
BRANCH=None
TEST=util/abuild/abuild -p none -t google/brya -x -a
make sure the build includes GOOGLE_REDRIX

Signed-off-by: Wisley Chen <wisley.chen@quanta.corp-partner.google.com>
Change-Id: I4cfa0bd84e1ba9f8140f95d18a6da960da8124ad
Reviewed-on: https://review.coreboot.org/c/coreboot/+/55883
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Reviewed-by: Nick Vaccaro <nvaccaro@google.com>