base_image_util.sh: probe unibuild based on presence of /usr/share/chromeos-config

JSON config is dead and being removed in CL:2065957. Drop this code
which requires the JSON config.

This was only ever used for specifying CHROMEOS_RELEASE_UNIBUILD=1 in
the lsb_release, so we never actually needed the list of supported
model names anyway.

BUG=chromium:1054199
TEST=build_image for unibuild, lsb_release contains
     CHROMEOS_RELEASE_UNIBUILD=1

Cq-Depend: chromium:2078954
Change-Id: I5f9853a1966c0cff792dc09ded298ae7c30aa40c
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosutils/+/2078934
Tested-by: Jack Rosenthal <jrosenth@chromium.org>
Reviewed-by: C Shapiro <shapiroc@chromium.org>
Reviewed-by: Chris McDonald <cjmcdonald@chromium.org>
Commit-Queue: Jack Rosenthal <jrosenth@chromium.org>
1 file changed