Adds EncryptAddToken=<type>[:<source>:<value>] to repart.d partition
files, registering one or more LUKS2 token objects in the partition
header after the keyslot is created. This allows custom token plugins
(e.g. a TDX KBS plugin) to be wired up at provisioning time without a
separate cryptsetup token import step.
The type name is always explicit and extra token fields can be supplied as
a JSON file (:file:/path) or base64-encoded JSON (:data:<base64>). The
type and keyslots fields are always injected by repart. The option is
repeatable; an empty value clears all tokens for the partition.
Supported with Encrypt=key-file, tpm2, and key-file+tpm2.