kernel-overlays.service needs to be ordered before the modprobe@
instances, which were introduced in systemd 245, otherwise
modprobe@drm.service can run before /lib/firmware exists and
edid-override will fail.
Fix that by adding modprobe@.service template drop-in to order it
after kernel-overlays.service
Signed-off-by: Matthias Reichl <hias@horus.com>
