X509_CRL_sign
LCRYPTO_USED(X509_CRL_sign);
int X509_CRL_sign(X509_CRL *x, EVP_PKEY *pkey, const EVP_MD *md);
LCRYPTO_ALIAS(X509_CRL_sign);
if (!X509_CRL_sign(xc, pkey, EVP_sha256()))