Modify the configuration file of telegraf

Influxdb is  standalone deployed by kolla-ansible,
The cluster mode is  charged now.
Previously configured, each telegraf monitors all influxdb.
If the telegraf is more, It is a disaster to influxdb.
So, telegraf should monitor influxdb deployed on the same server.

Change-Id: I9f4003a55de2a7be53c644b1d2f89d00cdf9478a