Update to anaconda-34.25.5.1
    
    anaconda-diskroot: wait before dying on media check fail (awilliam)
      Resolves: RHEL-4790
    Add ping tool to Dracut (jkonecny)
      Resolves: RHEL-5719
    gui:Fix index error for _remove_treeinfo_repositories() (liuwenyu.0311)
      Resolves: RHEL-29561