The previous flow was using TPM PCR 11 values to bound the policy which
means TPM cannot unseal when UKI changes. Now it's fixed to use PCR 7
which is bound to the SecureBoot state (SecureBoot status and
Certificates). This provides a full chain of trust bound to SecureBoot
state and signed PCR signature.
Also the code has been refactored to use PolicyCalculator from the TPM
library.
Signed-off-by: Noel Georgi <git@frezbo.dev>
