Bad max check when creating a new subscription

During the creation of a new subscription the number of active
subscriptions are compared to the maximum number of subscriptions
allowed to be created. However, this check validated against
number of received publish requests instead of number of
active subscriptions.

src/server/ua_services_subscription.c

@@ -71,7 +71,7 @@ Service_CreateSubscription(UA_Server *server, UA_Session *session,
                            UA_CreateSubscriptionResponse *response) {
     /* Check limits for the number of subscriptions */
     if((server->config.maxSubscriptionsPerSession != 0) &&
-       (session->numPublishReq >= server->config.maxSubscriptionsPerSession)) {
+       (session->numSubscriptions >= server->config.maxSubscriptionsPerSession)) {
         response->responseHeader.serviceResult = UA_STATUSCODE_BADTOOMANYSUBSCRIPTIONS;
         return;
     }