mb/google/fizz: Use variant-specific gma-mainboard.ads files

The karma variant, being a Chromebase, has an internal eDP output for
the built-in display whereas the fizz/endeavour variants do not. Use
separate gma-mainboard.ads files so that karma's internal panel works
properly with libgfxinit.

TEST=build google/fizz (fizz/karma) with libgfxinit enabled, ensure
correct gma-mainboard.ads file is included in the build.

Change-Id: Ia6aca538ba8c13b48aa80901222071d704b5f0c0
Signed-off-by: Matt DeVillier <matt.devillier@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/81901
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>

0 files changed, 0 insertions, 0 deletions