sys-boot/grub-lakitu: add SBAT revocation date to the EFI binary

Recent version of the EFI shim require GRUB binary to include
the .sbat section. This section is a CSV file that contains
information about the vendor, package, and version that can be used
by shim to decide whether the binary is trusted or not. More details:
  https://github.com/rhboot/shim/blob/main/SBAT.md

BUG=b/186856815
TEST=presubmit
RELEASE_NOTE=None

Change-Id: I4399f7460fa4a0efa6ddac0f0c37cffc2182b0d9
Reviewed-on: https://cos-review.googlesource.com/c/cos/overlays/board-overlays/+/27581
Reviewed-by: Oleksandr Tymoshenko <ovt@google.com>
Tested-by: Oleksandr Tymoshenko <ovt@google.com>
3 files changed