added ansible_pkg_mgr check for apt modules in test-setup-swifthosts.yml

it is necessary to check ansible_pkg_mgr = 'apt' when using apt modules

Change-Id: I2b09d3a38c1f6499fb93883fb9879206cdaff457

test-setup-swifthosts.yml

@@ -24,10 +24,14 @@
       state: present
     delegate_to: "{{ physical_host }}"
     run_once: true
+    when:
+      - ansible_pkg_mgr == 'apt'
   - name: Ensure xfsprogs is installed on containers
     apt:
       name: xfsprogs
       state: present
+    when:
+      - ansible_pkg_mgr == 'apt'
   - name: Openstack directory Create
     file:
       state: directory