File _servicedata of Package libbacktrace

<servicedata>
  <service name="tar_scm">
    <param name="url">https://github.com/ianlancetaylor/libbacktrace.git</param>
    <param name="changesrevision">14818b7783eeb9a56c3f0fca78cefd3143f8c5f6</param>
  </service>
</servicedata>