* scd/app-openpgp.c (wipe_and_free_string, wipe_and_free): Enable
functions.
(pin2hash_if_kdf): Change interface. The input PIN is not anymore
changed. Further there are no more assumptions about the length of
the provided buffer.
(verify_a_chv): Adjust for changed pin2hash_if_kdf.
(verify_chv2): Ditto
(verify_chv3): Ditto.
(do_change_pin): Ditto.
(do_sign): Ditto.
--
Note that this a part of the patch
63bda3aad8ec4163b0241f64e8b587d665d650c3 which we used in 2.4 to
implement a PIN cache. For easier backporting we need to add this
here.