Allow galera_client role to skip package installs

This patch adds the galera_client_package_install option which allows
the deployer to skip the installation of the galera_client packages, and
simply set up the /root/.my.cnf configuration file.

This is useful for deploying the client on hosts that already have
galera client configured, but still want the client configuration setup.
For example the galera_server role which can have a conflict when the
client and server repository version don't match.

Change-Id: I00d662a8afc7ddd4778787d31dc394a0ea3b1401

defaults/main.yml

@@ -26,6 +26,7 @@ galera_client_package_state: "latest"
 galera_client_pip_package_state: "latest"
 
 galera_client_drop_config_file: false
+galera_client_package_install: true
 
 galera_client_distro_package_pins: []
 

releasenotes/notes/galera-client-package-install-fd34423e293f5d8b.yaml

@@ -0,0 +1,9 @@
+---
+features:
+  - The ``galera_client_package_install`` option can now
+    be specified to handle whether packages are installed
+    as a result of the ``openstack-ansible-galera_client``
+    role running. This will default to ``true``, but can be
+    set to ``false`` to prevent package installs. This is
+    useful when deploying the ``my.cnf`` client configuration
+    file on hosts that already have Galera installed.

tasks/galera_client_install.yml

@@ -16,12 +16,14 @@
 - include: galera_client_install_apt.yml
   when:
     - ansible_pkg_mgr == 'apt'
+    - galera_client_package_install | bool
   tags:
     - install-apt
 
 - include: galera_client_install_yum.yml
   when:
     - ansible_pkg_mgr == 'yum'
+    - galera_client_package_install | bool
   tags:
     - install-yum
 
@@ -36,5 +38,7 @@
   until: install_packages|success
   retries: 5
   delay: 2
+  when:
+    - galera_client_package_install | bool
   tags:
     - galera-client-pip-packages