File _servicedata of Package libbacktrace

<servicedata>
  <service name="tar_scm">
    <param name="url">https://github.com/ianlancetaylor/libbacktrace.git</param>
    <param name="changesrevision">b9e40069c0b47a722286b94eb5231f7f05c08713</param>
  </service>
</servicedata>