drm-tests: avoid minigbm downstream api for mmap_test

BUG=b:282243659
TEST=mmap_test

Change-Id: I76a42af8a02f2c04a2cfece4554c2ea4a471c140
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/drm-tests/+/4531246
Commit-Queue: Yiwei Zhang <zzyiwei@chromium.org>
Reviewed-by: Dawn Han <dawnhan@google.com>
Tested-by: Yiwei Zhang <zzyiwei@chromium.org>
Reviewed-by: Andres Calderon Jaramillo <andrescj@chromium.org>
1 file changed