Ed25519 support with pkcs11-tool

[saper]

Hey, you might want to check the following out:

Nitrokey HSM2 - support for ed25519

The SmartCard-HSM relies on the CC-certified crypto library of the SmartMX2 security controller and that does not support ed25519. Unfortunately NXP has no plans to add support in that library, so we are unable to support that in our code either. There is also little demand from the markets for which this chip is produced (large scale card deployments like banking, government, health), so I’m not optimistic that the situation will change. Additionally, there is no real benefit of those curves …