gpg: Simplify the tofu interface by using the public key packet.
* g10/tofu.c (fingerprint_str): Remove. (tofu_register): Take a public key instead of a fingerprint as arg. Use hexfingerprint() to get a fpr from the PK. (tofu_get_validity): Ditto. (tofu_set_policy, tofu_get_policy): Simplify by using hexfingerprint. * g10/trustdb.c (tdb_get_validity_core): Pass the primary key PK to instead of the fingerprint to the tofu functions.
This change has the advantage that we are not bound to a specific
fingerprint length and will thus helps us to implement rfc4880bis.
- Signed-off-by: Werner Koch <wk@gnupg.org>