image_signing: Add sha1sum of the recovery key to VERSION.signer.

firmware_keys field in the HWID database also contains hash of recovery
key so need this information as well in order to deprecate firmware_keys
field.

BUG=chromium:763328
TEST=1) ~/trunk/src/platform/vboot_reference/scripts/image_signing/sign_official_build.sh
  recovery ./chromeos_10644.0.0_soraka_recovery_dev-channel_mp.bin
  ./src/platform/vboot_reference/tests/devkeys ./output.bin
2) verify output file - VERSION.signer.
BRANCH=None

Change-Id: If2be93723e95d46fc0546239695be27c3229275c
Reviewed-on: https://chromium-review.googlesource.com/1053334
Commit-Ready: Marco Chen <marcochen@chromium.org>
Tested-by: Marco Chen <marcochen@chromium.org>
Reviewed-by: Wei-Han Chen <stimim@chromium.org>
Reviewed-by: C Shapiro <shapiroc@google.com>
1 file changed