TPM2 / Systemd / LUKS

@ahkok @pixelgeek any input on that?

I managed at least to auto unlock a non root partition via tpm, but till now I did not manage to do it with the root partition. When I look at other distris guides it points to the initrd and dracut. But looking in
What is the best practice to customize initrd? it seems to point that features should be solved central.

What is needed / missing to get luks2 root auto unlock on boot with tpm2 going?