display_wipe_message.sh: avoid screen turning off

Avoid screen turning off while showing message

BUG=chromium:544021
TEST=1. run in-place wiping on Paine
     2. discharge battery for now period of time

Change-Id: I30161f786819cfb1a7dc602726aa31455346341b
Reviewed-on: https://chromium-review.googlesource.com/311905
Commit-Ready: Shun-Hsing Ou <shunhsingou@chromium.org>
Tested-by: Shun-Hsing Ou <shunhsingou@chromium.org>
Reviewed-by: Hung-Te Lin <hungte@chromium.org>
1 file changed