BZ 1114143 Added host provisioning cancel message when cancelled by the user

If a user canceled a host provision request the user was presented with "Add of new Host Request was cancelled by the user" created a new message for the host provision cancel action "Provision Host Request was cancelled by the user".

https://bugzilla.redhat.com/show_bug.cgi?id=1114143
Should `flas.host.host_provision_cancelled` be simplified to `flash.host.provision_cancelled`?