Remove extra newline from CMP mock server error and add TODO on using request template

Reviewed-by: NMatt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/11998)

apps/cmp.c

@@ -2996,7 +2996,7 @@ int cmp_main(int argc, char **argv)
             if (req != NULL) {
                 if (strcmp(path, "") != 0 && strcmp(path, "pkix/") != 0) {
                     (void)http_server_send_status(cbio, 404, "Not Found");
-                    CMP_err1("Expecting empty path or 'pkix/' but got '%s'\n",
+                    CMP_err1("Expecting empty path or 'pkix/' but got '%s'",
                              path);
                     OPENSSL_free(path);
                     OSSL_CMP_MSG_free(req);

apps/cmp_mock_srv.c

@@ -208,6 +208,7 @@ static OSSL_CMP_PKISI *process_cert_request(OSSL_CMP_SRV_CTX *srv_ctx,
     }
     if (ctx->certOut != NULL
             && (*certOut = X509_dup(ctx->certOut)) == NULL)
+        /* TODO better return a cert produced from data in request template */
         goto err;
     if (ctx->chainOut != NULL
             && (*chainOut = X509_chain_up_ref(ctx->chainOut)) == NULL)