cros_bundle_firmware: wipe empty regions early on

Also: tell cbfstool to force-overwrite CBFS regions (potentially with
new CBFS data) both for wiped and legacy (one of which will overwrite
rw-legacy).

BUG=chromium:595715
BRANCH=none
TEST=verify bit-equivalence of regions between image.bin and cb_with_fmap
with CL:397219 or similar.

Change-Id: I4ad2a97fcb9977607b35e4d3c323bfa81a827bfd
Signed-off-by: Patrick Georgi <pgeorgi@google.com>
Reviewed-on: https://chromium-review.googlesource.com/397124
Commit-Ready: Patrick Georgi <pgeorgi@chromium.org>
Tested-by: Patrick Georgi <pgeorgi@chromium.org>
Reviewed-by: Patrick Georgi <pgeorgi@chromium.org>
1 file changed