GlusterFS: Fix missing parameter for registry PVC

Signed-off-by: Jose A. Rivera <jarrpa@redhat.com>

roles/openshift_persistent_volumes/tasks/main.yml

@@ -23,6 +23,7 @@
     - name: "{{ openshift_hosted_registry_storage_volume_name }}-glusterfs-claim"
       capacity: "{{ openshift_hosted_registry_storage_volume_size }}"
       access_modes: "{{ openshift_hosted_registry_storage_access_modes }}"
+      storageclass: ""
   when: openshift_hosted_registry_storage_glusterfs_swap | default(False)
 
 - name: create standard pv and pvc lists