Use GnuPG 2.1 style pubkey algo format also for subkey lists.
* src/gpasubkeylist.c (SUBKEY_SIZE): Define only for old gpgme versions. (gpa_subkey_list_new): Ditto for "Size". (gpa_subkey_list_set_key): Use new algostr if possble.
- Signed-off-by: Werner Koch <wk@gnupg.org>