cr50 and hammer/common code are such different chips that reusing the
same first_response_pdu does not make much sense.
Instead, we can use 2 different headers, the updater knows which
response to expect based on USB product ID.
In the common code answer, we can reply with the EC version string,
as well as rollback information and key version ID, which will
be required for reliable updating.
BRANCH=none
BUG=b:35587171
BUG=b:36375666
TEST=usb_updater2 can update hammer, and read its version, rollback
version and key version.
Change-Id: I20b04070606767c71df3e6286d53e238e13375c0
Reviewed-on: https://chromium-review.googlesource.com/476452
Commit-Ready: Nicolas Boichat <drinkcat@chromium.org>
Tested-by: Nicolas Boichat <drinkcat@chromium.org>
Reviewed-by: Nick Sanders <nsanders@chromium.org>
Reviewed-by: Nicolas Boichat <drinkcat@chromium.org>