Revert "Revert "Optionally (dis)allow degenerate DICE chains in ..."

Revert submission 3260534-revert-3254876-disallow_degenerate_chains-RZRFZAKDEJ

Reason for revert: Breakage fixed

Reverted changes: /q/submissionid:3260534-revert-3254876-disallow_degenerate_chains-RZRFZAKDEJ

Change-Id: I972b9b0cae932cc39be3f8d44ac59f82e878ca53
3 files changed