Ensure 0755 default mode on new directories

This patch ensures that all directories under `/openstack/venvs`
are created with `0755` permissions by default. This prevents
permission denied errors when running certain commands from the
virtual environment..

Change-Id: I77526b0ee556f5c219e59e4a2b3f9b92157de0d7

tasks/designate_install.yml

@@ -57,6 +57,7 @@
   file:
     path: "{{ designate_bin | dirname }}"
     state: directory
+    mode: "0755"
   register: designate_venv_dir
   when:
     - not designate_developer_mode | bool

tasks/designate_pre_install.yml

@@ -37,6 +37,7 @@
     group: "{{ item.group|default(designate_system_group_name) }}"
     mode: "{{ item.mode|default('0755') }}"
   with_items:
+    - { path: "/openstack/venvs", mode: "0755", owner: "root", group: "root" }
     - { path: "/etc/designate" }
     - { path: "/etc/designate/rootwrap.d", owner: "root", group: "root" }
     - { path: "/etc/sudoers.d", mode: "0750", owner: "root", group: "root" }