Haproxy binds the elasticsearch service to kolla_internal_vip_address but
the output templates for fluentd (td-agent) point to a non-existent
kolla_external_vip_address.
Output should also be able to be sent to an external elasticsearch
instance (as per the documentation regarding overriding
elasticsearch_address)
Change these settings so that fluentd outputs to either
the default elasticsearch_address (i.e. kolla_internal_vip_address) or to
the external elasticsearch instance.
Closes-Bug: #1673990
Change-Id: I081533ae8ea9aad186e9c44e1dee069729931453