cipher:kem:ecc: Support secp256k1 by KEM API.
* src/gcrypt.h.in (GCRY_KEM_RAW_P256K1): New. * cipher/kem-ecc.c (algo_to_curve, algo_to_seckey_len): Support GCRY_KEM_RAW_P256K1.
Cherry-picked from master commit of:
10c0ce88ba3fbba6b04ee6ded9d0f6ae15171d6b
- GnuPG-bug-id: T7698
- Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>