Comment 4 for bug 1849350

Reviewed: https://review.opendev.org/690471
Committed: https://git.openstack.org/cgit/openstack/tripleo-common/commit/?id=0eb79d311e129dbd596818b7ba83fbd0ab26a999
Submitter: Zuul
Branch: stable/train

commit 0eb79d311e129dbd596818b7ba83fbd0ab26a999
Author: Harald Jensås <email address hidden>
Date: Tue Oct 22 18:06:42 2019 +0200

    get_undercloud_registry() - Default to: 'localhost:8787'

    Standalone deployment does not have hosts entries. We cannot
    raise an error if the ctlplane entry is not present.

    This change reverts the function to return 'localhost' by default
    which was the behaviour prior to: https://review.opendev.org/687305

    Closes-Bug: #1849350
    Change-Id: Iba03ac88fa56d77d9f350b6c7f7d0c4276c104f4
    (cherry picked from commit 7ca3a550b159717a4cbb49d8b31f93f8c48964fc)