__bign_sign_finalize
ATTRIBUTE_WARN_UNUSED_RET int __bign_sign_finalize(struct ec_sign_context *ctx, u8 *sig, u8 siglen, ec_alg_type key_type);
return __bign_sign_finalize(ctx, sig, siglen, BIGN);
ret = __bign_sign_finalize(ctx, sig, siglen, DBIGN);