tpm2.target was functionally useless without these services and this
generator. When systemd-cryptsetup-generator creates
systemd-cryptsetup@.service units, they are ordered after
systemd-tpm2-setup-early.service, not tpm2.target. These services are
themselves ordered after tpm2.target.
Note: The systemd-tpm2-setup(-early) services will serve no *function*
under a normal NixOS system at the moment. Because of their
ConditionSecurity=measured-uki, they will always be skipped, unless
you are building an appliance with the system.build.uki feature. Thus,
these are enabled solely for their systemd unit ordering properties.
