Fix swift bare variable warning

[DEPRECATION WARNING]: evaluating 'swift_raw_disks' as a bare variable,
this behaviour will go away and you might need to add |bool to the
expression in the future. Also see CONDITIONAL_BARE_VARS configuration
toggle. This feature will be removed in version 2.12. Deprecation
warnings can be disabled by setting deprecation_warnings=False in
ansible.cfg.

Change-Id: I1d99dccc3ad8c6550581e69d48c7e7b365d53c7a

deployment/swift/swift-storage-container-puppet.yaml

@@ -621,14 +621,14 @@ outputs:
             dev: "{{ swift_raw_disks[item]['base_dir']|default('/dev') }}/{{ item }}"
             opts: -f -i size=1024
           with_items: "{{ swift_raw_disks }}"
-          when: swift_raw_disks
+          when: swift_raw_disks|length > 0
         - name: Refresh facts if SwiftRawDisks is set to get uuids if newly created partitions
           setup:
             gather_subset:
               - '!all'
               - '!min'
               - 'hardware'
-          when: swift_raw_disks
+          when: swift_raw_disks|length > 0
         - name: Mount devices defined in SwiftRawDisks
           mount:
             name: /srv/node/{{ item }}
@@ -637,7 +637,7 @@ outputs:
             opts: noatime
             state: mounted
           with_items: "{{ swift_raw_disks }}"
-          when: swift_raw_disks
+          when: swift_raw_disks|length > 0
       deploy_steps_tasks:
         - name: Configure rsyslog for swift-storage
           when: