remote: Set eventID explicitly to an invalid value

Set the eventID for remoteRelayDomainQemuMonitorEvent explicitly to an
invalid value. Although the value is not used by
remoteRelayDomainQemuMonitorEvent, but it might be less prone to
errors for further refactorings.
Signed-off-by: NMarc Hartmayer <mhartmay@linux.vnet.ibm.com>
Reviewed-by: NBjoern Walk <bwalk@linux.vnet.ibm.com>
Reviewed-by: NBoris Fiuczynski <fiuczy@linux.vnet.ibm.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>

src/remote/remote_daemon_dispatch.c

@@ -6215,6 +6215,7 @@ qemuDispatchConnectDomainMonitorEventRegister(virNetServerPtr server ATTRIBUTE_U
     if (VIR_ALLOC(callback) < 0)
         goto cleanup;
     callback->client = virObjectRef(client);
+    callback->eventID = -1;
     callback->callbackID = -1;
     ref = callback;
     if (VIR_APPEND_ELEMENT(priv->qemuEventCallbacks,