Remove read only disks from lvm candidates
Remove read only disks from lvm candidates

This patch removes read only disks from the candidates to be used
to store the lxc and cinder lvm volume groups.

Change-Id: I8fc0842f3629ac3c9fd01b01ecf37ffc68e3b871
Closes-Bug: #1487055
(cherry picked from commit 979c876378d30e0bba78de370b2b0dbd967149cf)

VaneCloud/openstack-ansible,yanyao/openstack-deployment,VaneCloud/openstack-ansible,yanyao/openstack-deployment,yanyao/openstack-deployment,yanyao/openstack-deployment,VaneCloud/openstack-ansible