This fixes a regression from 
b6455ee: 'packages' variable
is injected in 'firewall' role by package_facts module with
a higher priority than variable of same name defined in 'docker'
roles' defaults.
Change-Id: I41e0f992ceaab871ae38fb1b8211fd71c042c9b2
Issue-ID: INT-1578
Signed-off-by: Bartek Grzybowski <b.grzybowski@partner.samsung.com>
 docker:
   log_max_size: 100m
   log_max_file: 3
-packages:
+custom_packages:
   RedHat:
     - python-docker-py
     - python-jsonpointer
 
   package:
     name: "{{ item }}"
     state: present
-  loop: "{{ packages[ansible_os_family] }}"
+  loop: "{{ custom_packages[ansible_os_family] }}"
 
 - name: Ensure /etc/docker exists
   file: