chromeos-bootimage: Add clapper to BOARDS

BUG=chrome-os-partner:25046
TEST=build only

Change-Id: Iddf395353942d43e20ab0c9ce14305300ca465ae
Reviewed-on: https://chromium-review.googlesource.com/182666
Reviewed-by: Gediminas Ramanauskas <gedis@chromium.org>
Commit-Queue: Shawn Nematbakhsh <shawnn@chromium.org>
Tested-by: Shawn Nematbakhsh <shawnn@chromium.org>
2 files changed