Since used_memslots will be updated to the actual value after
registering memory listener for the first time, move the
memslots limit checking to the right place.
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Jay Zhou <jianjay.zhou@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>