board/asurada: Show firmware sync screen

Set CONFIG_EC_SLOW_UPDATE so that firmware sync screen will be shown
during EC sync. On Hayato, EC sync takes about 7 seconds to complete.

BUG=none
TEST=emerge-asurada depthcharge
BRANCH=asurada

Change-Id: Id7021ac818473c9f6a1dc8a20477e40f55b355ed
Signed-off-by: Yu-Ping Wu <yupingso@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/depthcharge/+/2763788
Reviewed-by: Hung-Te Lin <hungte@chromium.org>
1 file changed