community/xorg-server: revert dpi calculation changes that leads to more issues than it fixes
The result of this change was everything being wrongly scaled and way too big. Other distros have already reverted it, let's do the same
https://gitlab.freedesktop.org/xorg/xserver/-/issues/1241
Upstreaming is reverting the change too in upcoming 21.1.2
https://gitlab.freedesktop.org/xorg/xserver/-/issues/1241#note_1153655