Fix CentOS swap creation
Fix CentOS swap creation

The bootstrap_host_swap_size variable contains a string and it is
being repeated 1024 times. This patch ensures that the variable
returns an integer so that it is calculated properly.

Change-Id: I0f1da21482f29e112bc6a96cd57654c631ac0f61

robb-romans/openstack-ansible,yanyao/openstack-ansible,cfarquhar/openstack-ansible,bunchc/openstack-ansible,bunchc/openstack-ansible,openstack/openstack-ansible,yanyao/openstack-ansible,openstack/openstack-ansible,cloudnull/os-ansible-deployment,cloudnull/os-ansible-deployment,cfarquhar/openstack-ansible,stackforge/os-ansible-deployment,robb-romans/openstack-ansible,stackforge/os-ansible-deployment