lxc: Do not try to reconnect inactive domain when do lxcStartup

Otherwise if there are inactive lxc domains, lxcStartup will
try to reconnect to sockets of these domains, which results in
errors in libvirtd log.

src/lxc/lxc_driver.c

@@ -1992,6 +1992,9 @@ lxcReconnectVM(void *payload, const void *name ATTRIBUTE_UNUSED, void *opaque)
 
     virDomainObjLock(vm);
 
+    if (!virDomainObjIsActive(vm))
+        goto cleanup;
+
     priv = vm->privateData;
     if ((priv->monitor = lxcMonitorClient(driver, vm)) < 0) {
         goto cleanup;