File _servicedata of Package opencl-headers

<servicedata>
<service name="tar_scm">
            <param name="url">https://github.com/KhronosGroup/OpenCL-Headers.git</param>
          <param name="changesrevision">4fdcfb0ae675f2f63a9add9552e0af62c2b4ed30</param></service></servicedata>