gpg: Remove extra RSA import status line.

* g10/import.c (stats_s): Remove field "imported_rsa".
(import_print_stats): Do not print separate value for RSA.
(import_one): Remove the RSA counter.

RSA is the standard key format and thus there is no more need to have
a separate counter. This is a remain from the RSA patent times.

• Signed-off-by: Werner Koch <wk@gnupg.org>