vboot2: Add sd->fw_version_secdata field to communicate to crossystem

This patchs adds a new vb2_shared_data field to store the current
rollback prevention version number stored in secdata (TPM). This
information needs to be retrieved from there by coreboot (current
hack) or vboot2 kernel verification (bright shiny future) so it can be
passed along to the operating system and user space.

TEST=make runtests. Booted Jerry in recovery mode (with corresponding
coreboot patch), ensured that crossystem tpm_fwver still shows the
correct value.

Change-Id: I2a0c3e51b158a35ac129d2abce19b40c6c6381a6
Signed-off-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/244601
Reviewed-by: Randall Spangler <rspangler@chromium.org>
6 files changed