Kdrive X servers used to do the OS-speciffic init part using KdOsInit.
This was changed in modern Xorg because Xephyr is the only kdrive
X server there, so there was no need to keep this generic.
Since we want to eventually add Xfbdev, we need to add this back.
Signed-off-by: stefan11111 <stefan11111@shitposting.expert>