Support for TSS2 keys

[arunoruto]

I came across the ssh-tpm-agent and it provides a method to generate keys via the TPM on the client device. With that, we can have host keys which are really tied to the host and also provide host tied user keys.
The ssh-tpm-agent can provide ECDSA and RSA keys, but they are not based on OpenSSH, but on TSS2. I was wondering, if the RSA key could be translated to a PGP key via ssh-to-pgp, which would be a great addition for sops-nix.

[Mic92]

Unsure. Isn't the Idea usually that the key material stays in the TPM? This would not work in this case. However there is https://github.com/Foxboron/age-plugin-tpm which can be supported.