scd: Add handling of "Algorithm Information" DO.

* cd/app-openpgp.c (data_objects): Add 0x00FA.
(do_getattr): Add KEY-ATTR-INFO.

See the section 4.4.3.11 Algorithm Information in the OpenPGP card
functional specification version 3.4.1.

• Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>