Fix distro installs

Ubuntu distro packages change /etc/swift/ owner to root, which makes
swift_rings.py fail with Permission denied.
So we shouldt run swift_rings.py as root user for distro deployments.

Change-Id: I3eeec29de43a3fb80bafef104ac87348aca4853e

tasks/swift_rings_build.yml

@@ -43,6 +43,15 @@
     - "{{ swift.storage_policies }}"
     - [{ type: 'object', port: "{{ swift_object_port }}" }]
 
+- name: Ensure swift config directory permissions
+  file:
+    path: /etc/swift/
+    state: directory
+    owner: "{{ swift_system_user_name }}"
+    group: "{{ swift_system_group_name }}"
+    recurse: yes
+  when: swift_install_method == 'distro'
+
 - name: "Build rings for account/container from contents files"
   command: "/etc/swift/scripts/swift_rings.py -f /etc/swift/scripts/{{ item[0] }}.contents{% if item[1] %} -r {{ item[1] }}{% endif %}{{ (swift_pretend_min_part_hours_passed | bool) | ternary(' -p', '')}}"
   with_nested: