disable yast2-x11 during installation (bnc#441404) 2.18.21
disable yast2-x11 during installation (bnc#441404)
2.18.21

svn path=/trunk/installation/; revision=58225

kobliha/skelcd-control-openSUSE,jsrain/skelcd-control-SLES,yast/skelcd-control-SLES,yast/skelcd-control-SLES,jsrain/skelcd-control-SLES,yast/skelcd-control-SLED,yast/skelcd-control-SLED,kobliha/skelcd-control-openSUSE,sndirsch/skelcd-control-openSUSE,bmwiedemann/skelcd-control-openSUSE,yast/skelcd-control-openSUSE,dirkmueller/skelcd-control-openSUSE,lnussel/skelcd-control-openSUSE,yast/skelcd-control-openSUSE,bmwiedemann/skelcd-control-openSUSE,sndirsch/skelcd-control-openSUSE,lnussel/skelcd-control-openSUSE,dirkmueller/skelcd-control-openSUSE