Bug#838899: xorg: debian 9 Xorg -configure generated xorg.conf breaks lightdm on video-vmware and video-dummy

[Hans Henrik Bergan]

there was recently an update to.. among other things,
xserver-xorg-video-core i believe. in any case, i just did "apt-get update;
apt-get upgrade; apt-get dist-upgrade;" , noticed there was xorg-related
updates, tested again, and xserver-xorg-video-dummy works again now it
seems :)