Fix permissions of kolla-ansible target virtualenv

When using a target virtual environment for kolla-ansible [1], it is possible
to get a Permission Denied error. This can occur if the permissions of
/opt/kayobe or /opt/kayobe/venvs are restricted to the stack user (0700), since
kolla ansible uses the kolla user.

Although it makes sense for /opt/kayobe/venvs/kayobe to be 0700, /opt/kayobe
and /opt/kayobe/venvs should be 0755 to allow the kolla user to access a
virtualenv in /opt/kayobe/venvs/kolla-ansible.

This was seen during deployment of a seed, with kayobe target virtualenvs [2]
also in use. Since the kayobe-target-venv.yml playbook is one of the first
playbooks to be run, it will create the /opt/kayobe and /opt/kayobe/venvs
directories, and set the permissions correctly.

[1] http://kayobe.readthedocs.io/en/latest/configuration/kolla-ansible.html#remote-execution-environment
[2] http://kayobe.readthedocs.io/en/latest/configuration/kayobe.html#remote-execution-environment

Change-Id: I124cff8f08309c1eeef78c035c4cf195367b21f2
Story: 2001968
Task: 15868

ansible/kayobe-target-venv.yml

@@ -28,6 +28,18 @@
             state: installed
           become: True
 
+        - name: Ensure global virtualenv directory exists
+          file:
+            path: "{{ virtualenv_path }}"
+            state: directory
+            owner: "{{ ansible_user }}"
+            group: "{{ ansible_user }}"
+            mode: 0755
+          # Check whether the virtualenv directory is a subdirectory of the
+          # global virtualenv directory.
+          when: virtualenv.startswith(virtualenv_path)
+          become: True
+
         - name: Ensure kayobe virtualenv directory exists
           file:
             path: "{{ virtualenv }}"