File _servicedata of Package libbacktrace

<servicedata>
  <service name="tar_scm">
    <param name="url">https://github.com/ianlancetaylor/libbacktrace.git</param>
    <param name="changesrevision">f41cf1fecbc01966e0a3c32a1a54ff9cb0a19bb9</param>
  </service>
</servicedata>