Add ability to disable serial throttling for mnaio installs

This allows the setting of an ansible osa_disable_serial variable
  that drops in a config to set all of the serial settings to 100%
  to disable throttling.  The exception being keystone as it has a
  race condition that prevents it.  The default is 'false' and can
  be set in the MNAIO_ANSIBLE_PARAMETERS var before running the
  build.sh script.

Change-Id: I5850d882d465b7ef10b317076bb135934f1ceba2
Closes-Bug: 1752475

multi-node-aio/playbooks/deploy-osa.yml

@@ -79,6 +79,17 @@
       when:
         - pre_config_osa | default(true) | bool
 
+    - name: Drop config to disable serial throttle settings
+      template:
+        src: "osa/user_unserial_variables.yml"
+        dest: /etc/openstack_deploy/user_unserial_variables.yml
+        mode: "0644"
+        owner: root
+        group: root
+      when:
+        - pre_config_osa | default(true) | bool
+        - osa_disable_serial | default(false) | bool
+
     - name: Ensure the user_variables file is populated
       lineinfile:
         path: /etc/openstack_deploy/user_variables.yml

multi-node-aio/playbooks/group_vars/all.yml

@@ -126,3 +126,4 @@ osa_enable_dashboard: true
 osa_enable_network: true
 osa_enable_meter: true
 osa_enable_object_storage: true
+osa_disable_serial: false

multi-node-aio/playbooks/osa/user_unserial_variables.yml

@@ -0,0 +1,16 @@
+cinder_api_serial: 100%
+cinder_scheduler_serial: 100%
+cinder_backend_serial: 100%
+glance_api_serial: 100%
+glance_registry_serial: 100%
+neutron_server_serial: 100%
+neutron_agent_serial: 100%
+neutron_other_serial: 100%
+nova_conductor_serial: 100%
+nova_scheduler_serial: 100%
+nova_api_serial: 100%
+nova_console_serial: 100%
+nova_compute_serial: 100%
+nova_serial: 100%
+#keystone_serial: 100%  # Do NOT enable due to race condition with authorized_keys module.
+