File _servicedata of Package ipxe

<servicedata>
  <service name="tar_scm">
    <param name="url">https://github.com/ipxe/ipxe.git</param>
    <param name="changesrevision">764e34f15af89cc7c5e46694ac15c5266f13b3d3</param>
  </service>
</servicedata>