update_kernel: Check buildid to confirm update went through

Let's add a check to the end of the update process that checks to make
sure the new kernel matches the kernel in /build/${BOARD} that we were
copying over. Rely on the buildid to match between the two by comparing
the .notes section (which contains the buildid) and printing an error
if they don't match.

TEST=./update_kernel.sh --remote=$DUT

Change-Id: I0a6836883cb768b7a94a1ca2d8dfe4741cb323ff
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosutils/+/3439131
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Stephen Boyd <swboyd@chromium.org>
Commit-Queue: Stephen Boyd <swboyd@chromium.org>
1 file changed