Revert "Fix ssh_known_hosts hostname entries"

This reverts commit a5bcbc8d01.

This looks to have broken ovb.

2019-11-12 17:28:30 | The error appears to be in '/usr/share/ansible/roles/tripleo-ssh-known-hosts/tasks/main.yml': line 46, column 7

Change-Id: I26e3753ad438ae1c358be372318ade231d8b1d93

releasenotes/notes/fix_ssh-known-hosts-2520b9d6f67458b7.yaml

@@ -1,10 +0,0 @@
----
-fixes:
-  - |
-    Previously the tripleo-ssh-known-hosts ansible role used the list of
-    network names to create the different possible hostnames in the
-    ssh_known_hosts file. The network names do not match the actual network
-    hostnames, like internal_api vs. internalapi which results in ssh host
-    verification to fail and e.g. live migration to fail.
-    This changes to use the _hostname inventory information to be used to add
-    hostname information to the ssh_known_hosts file.

tripleo_ansible/roles/tripleo-ssh-known-hosts/tasks/main.yml

@@ -52,8 +52,8 @@
           {%- if enabled_networks | length > 0 and role_networks and role_networks | length > 0 %},
           {%- for network in enabled_networks %}
           {%- if network in role_networks %}
-          [{{ hostvars[host][networks[network]['name'] ~ '_ip'] }}]*,[{{ host }}.{{ networks[network]['name'] | replace("_", "") }}]*,{% if 1 %}{% endif %}
+          [{{ hostvars[host][networks[network]['name'] ~ '_ip'] }}]*,[{{ host }}.{{ networks[network]['name'] }}]*,{% if 1 %}{% endif %}
-          [{{ hostvars[host][networks[network]['name'] ~ '_hostname'] }}]*{% if not loop.last %},{% endif %}
+          [{{ host }}.{{ networks[network]['name'] }}.{{ cloud_domain }}]*{% if not loop.last %},{% endif %}
           {%- endif -%}
           {%- endfor -%}
           {%- endif -%}