futility: updater: Add new quirk 'allow_empty_wltag'

There were devices shipped as "only device" (no key set) and then became
one of the "white label" family. This is now no longer valid on newer
devices but we have to support the legacy ones, for example Reks.

BUG=chromium:906962
TEST=make futil; tests/futility/run_test_scripts.sh $(pwd)/build/futility
BRANCH=None

Change-Id: I437be08726ab2c46229062689bf765ac6837ca5d
Signed-off-by: Hung-Te Lin <hungte@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/1345610
Reviewed-by: Youcheng Syu <youcheng@chromium.org>
4 files changed