2lib: Add vb2api_is_developer_signed() to replace old dev key check

This patch removes the old check for developer keys from the firmware
verification path and instead inserts a similar (but faster) check into
vb2api_kernel_phase1(). This has the advantage that we can export the
check function to the calling firmware which could use it to display
this information in a more user-visible manner.

BRANCH=None
BUG=None
TEST=Booted in normal and recovery mode with developer keys, confirmed
they were recognized.

Change-Id: I00af0d10e31b2789574c8e4f1875ccd8d01eb0d5
Signed-off-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/vboot_reference/+/2038245
Reviewed-by: Joel Kitching <kitching@chromium.org>
3 files changed