How to clean up the Elasticsearch settings?

I made the following setting to my Elasticsearch cluster in order to decommission some old nodes in the cluster. After removed these old nodes, now I need to re-enable cluster to allocate shards on those '10.0.6.*' nodes. Does anyone know how to remove this setting?

PUT /_cluster/settings
{
   "transient": {
      "cluster.routing.allocation.exclude._ip": "10.0.6.*"
   }
}

Thanks in advance for any help!