Fixed stackviz report for standalone

* When Moving 'stackviz to /var/log/extra/stackviz' task is called,
  /var/log/extra/stackviz directory does not exist which leads to
  failure giving no such directory in order to fix that we need
  to check whether destination exists or not. If not first create
  it and then move the content and also make sure stackviz-export
  operation has successfully completed.

Change-Id: Ie84c150c74363da25e76bbb234a864a72c6c366a

roles/validate-tempest/tasks/stackviz.yml

@@ -30,9 +30,20 @@
     set -o pipefail
     source "{{ working_dir }}/tempest/.stackviz/bin/activate"
     stackviz-export {{ tempest_dstat_opt | default('') }} --env -f {{ working_dir }}/tempest/testrepository.subunit {{ working_dir }}/stackviz/data
+  register: stackviz_result
   args:
       chdir: "{{ working_dir }}/tempest"
 
-- name: Moving stackviz to /var/log/extra
-  shell: mv {{ working_dir }}/stackviz/ /var/log/extra/stackviz
+- name: Ensure /var/log/extra exists
+  file:
+    path: /var/log/extra
+    state: directory
+    mode: 0755
   become: true
+
+- name: Moving stackviz to /var/log/extra
+  shell: |
+    set -o pipefail
+    mv {{ working_dir }}/stackviz/ /var/log/extra
+  become: true
+  when: stackviz_result.rc == 0