Calling the kodi-xxx target in ExecStart= was not actually the key to
fixing the shutdown bugs in 847b6ec65. Adding the ExecStop= calling
killall to the exact target was needed.
This commit restores the call to kodi-standalone to allow the
"RestartApp" built in to work again and adds the key ExecStop= with
killall.
Use the same dependencies and their order in both systemd units.
Add additional units of services that kodi uses.
Don't use "Requires=", kodi can run without a network connection.
Export WINDOWING=x11 in kodi.service to skip the autodetection that /usr/bin/kodi-standalone performs.
Give kodi-gbm.service the privileges of input group, this allows removing the kodi user from that group's membership since kodi.service does not need it.
