File _servicedata of Package libsigrok

<servicedata>
  <service name="tar_scm">
    <param name="url">https://github.com/sigrokproject/libsigrok.git</param>
    <param name="changesrevision">0bc2487778e660f4d3116729b6f4aee2b1996bb0</param>
  </service>
</servicedata>