When Toad's ID changes, VBUS goes low for 10ms. This, however, is not
picked up by TSU6721 and thus we need to monitor VBUS and reset TSU6721
when necessary. By resetting TSU6721, we can force it to update device
type.
BUG=chrome-os-partner:18292
TEST=manual
BRANCH=spring
Change-Id: Ib96bbb0f101c8c5f5371591603af2dee27f01cc8
Signed-off-by: Vic Yang <victoryang@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/45727