sign_uefi.sh:Port google3 changes required for COS

As part of the Cusky signing design, we carry custom changes to the
sign_uefi.sh script in a fork of vboot_reference repository on google3.
To move the signing behavior from the BC to the BE, we will need to
port those changes from google3 to here.

The custom changes being ported here are the ones made in cl/316911016,
cl/317144168 and cl/318860928.

BUG=b/170128847
TEST=presubmit; merged signer container with BE container, patched these
changes in and ran this script (via sign_official_build.sh in
go/cos-rev/c/18671)

Change-Id: Id3ecd8b5cf056d244f8cfd89f65d9f13322b0998
Reviewed-on: https://cos-review.googlesource.com/c/third_party/platform/vboot_reference/+/18670
Tested-by: Cusky Presubmit Bot <presubmit@cos-infra-prod.iam.gserviceaccount.com>
Reviewed-by: Robert Kolchmeyer <rkolchmeyer@google.com>
Reviewed-on: https://cos-review.googlesource.com/c/third_party/platform/vboot_reference/+/21902
Tested-by: Cusky QA Presubmit Bot <presubmit@cos-infra-prototype.iam.gserviceaccount.com>
1 file changed