ecc: Fix initialization of CTX for sign and verify.
* cipher/ecc.c (ecc_sign, ecc_verify): Call _gcry_pk_util_init_encoding_ctx at first.
- Reported-by: Vladimir Lomov <lomov.vl@yandex.ru>
- GnuPG-bug-id: T5267
- Fixes-commit: d51a9c259d49c63121fab48bce48d826e9b57733
- Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>