* sm/keydb.c (kbx_client_set_ephemeral): New.
(keydb_set_ephemeral): Implement the keyboxd use case.
(set_cert_flags): Rename from keydb_set_cert_flags for the case
of local keybox access.
(keydb_set_cert_flags): Implement the keyboxd use case.
(keydb_clear_some_cert_flags): Implement the keyboxd use case.