* Added new `WOLFBOOT_TPM_SEAL` and `WOLFBOOT_TPM_SEAL_NV_BASE` config options.
* Added new `tools/tpm/policy_create` tool for assisting with creation of a policy digest. The sign keytool `--policy=file` signs the policy.
* Added new `WOLFBOOT_TPM_VERIFY` option to enable offloading of the asymmetric verification to the TPM. By default wolfCrypt will be used.
* Added example seal/unseal to update_flash for ARCH_SIM.
* Renamed `WOLFBOOT_TPM_KEYSTORE_NV_INDEX` to `WOLFBOOT_TPM_KEYSTORE_NV_BASE` to support multiple public keys.
* Refactored most TPM code into tpm.c.
* Refactored the keystore ROT to use new `wolfBoot_check_rot` API.
* Refactored the sign keytool to have a sign_digest function to allow signing firmware and policy for sealing/unsealing.
* Fix for make distclean && make using the wrong key tools.
Marco Oliverio
Daniele Lacamera
David Garske