updater_utils.h: stop using 'dev=1' in flashrom command

Replace 'ec:dev=1' with equivalent 'ec:type=pd'.

BUG=b:153024532
BRANCH=none
TEST=emerge vboot_reference

Change-Id: Ic8df99fcdc3769bec19054b1936b97b14bade0e7
Signed-off-by: Nikolai Artemiev <nartemiev@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/2151492
Reviewed-by: Hung-Te Lin <hungte@chromium.org>
Reviewed-by: Edward O'Callaghan <quasisec@chromium.org>
Tested-by: Edward O'Callaghan <quasisec@chromium.org>