init: fix ply-image parameter in wiping command (only in R12)

The ply-image changed its usae syntax and there's a bug (or feature?) that image
without (x,y) location can't be displayed. This is a temporary fix (for R12) for
wiping.

ToT should fix this in ply-image intead of chromeos_startup.

BUG=chromium-os:15059
TEST=echo "factory fast" > /mnt/stateful_partition/factory_install_reset
     cp wipe_splash.png /mnt/stateful_partition/.
     reboot # seeing wipe_splash shown

Change-Id: I6df17117b4e946d609f7e118cb19a597fa53e4fc
Reviewed-on: http://gerrit.chromium.org/gerrit/526
Reviewed-by: Hung-Te Lin <hungte@chromium.org>
Tested-by: Hung-Te Lin <hungte@chromium.org>
1 file changed