CT_POLICY_EVAL_CTX_set1_issuer
int CT_POLICY_EVAL_CTX_set1_issuer(CT_POLICY_EVAL_CTX *ctx, X509 *issuer);
CT_POLICY_EVAL_CTX_set1_issuer(ctx, issuer);
CT_POLICY_EVAL_CTX_set1_issuer(ct_policy_ctx, issuer);