* Support for external keys (CryptoCb interface)
* Support for usage in mutual authentication
* better entity cert parsing
* Fix for Zephyr port to support the feature
* Check key support
* Proper validation of signatures in certificate chains
* Proper validation of peer cert with local issuer signature
(alt pub key is cached now)
* Support for ECC & RSA as alt keys with PQC as primary
* Support for PQC certificate generation
* Better support for hybrid signatures with variable length signatures
* Support for primary and alternative private keys in a single
file/buffer
* More API support for alternative private keys
Signed-off-by: Tobias Frauenschläger <t.frauenschlaeger@me.com>