test_image_util.sh: Copy DLC(s) for test images

build_dlc.py allows for filtering of DLC(s) built with preloading
capability and should be used to selectively copy DLC(s) that are
required for testing.

BUG=chromium:1037659
TEST=./build_image --board=$B --noenable_rootfs_verification test
Cq-Depend: chromium:1993689
Change-Id: I3e606db5b0da446d42f6f94621337877b7fa10d3
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosutils/+/1994140
Tested-by: Jae Hoon Kim <kimjae@chromium.org>
Reviewed-by: Amin Hassani <ahassani@chromium.org>
Reviewed-by: Andrew Lassalle <andrewlassalle@chromium.org>
Reviewed-by: Chris McDonald <cjmcdonald@chromium.org>
Commit-Queue: Jae Hoon Kim <kimjae@chromium.org>
1 file changed