Fixes device cleanup with driver domains in use (non-dom0 backend). The issue is the backend domain ID hasn't been explicitly specified, defaulting to 0, causing device cleanup to silently fail. However for a live domain the backend domain ID/path is present in the xenstore and thus can be unambigiously identified by the domU.
Fixes device cleanup with driver domains in use (non-dom0 backend). The issue is the backend domain ID hasn't been explicitly specified, defaulting to 0, causing device cleanup to silently fail. However for a live domain the backend domain ID/path is present in the xenstore and thus can be unambigiously identified by the domU.