* scd/app-openpgp.c (data_objects): Special DOs like "Login Data",
"URL", "Private DO N" can be longer size >= 256.
(struct app_local_s): Define bits for v3 card.
(get_cached_data): Use extcap.max_special_do for special DOs.
(app_select_openpgp): Detect if extcap_v3, kdf_do, and other bits.