Moved sampling of ALS to its own task. The problem is that it
spin waits on the i2c bus mutex, and it's a bad idea to spin wait
for very long in the hooks task because the hooks task tickles
the watchdog.
BUG=chrome-os-partner:29003
BRANCH=none
TEST=tested on samus: make sure ALS task is running and no
watchdog timeouts when the i2c bus is wedged indefinitely.
Change-Id: Ifcebabdfc151ea85cecdfe7a8ed489e8a82ee5ba
Signed-off-by: Alec Berg <alecaberg@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/202545
Reviewed-by: Randall Spangler <rspangler@chromium.org>