* scd/app-openpgp.c (key_type_t): New.
(CURVE_NIST_P256, CURVE_NIST_P384, CURVE_NIST_P521): New.
(struct app_local_s): Change keyattr to have key_type and union.
(get_ecc_key_parameters, get_curve_name): New.
(send_key_attr, get_public_key): Support ECDSA.
(build_privkey_template, do_writekey, do_genkey): Follow the change
of the member KEY_ATTR.
(parse_historical): New.
(parse_algorithm_attribute): Support ECDSA.