X server: Enable local access control

For the last ten years we have been passing -ac to the X server, which
is very bad idea.

Fixes #14623.

Changed files
+1 -2
nixos
modules
services
+1 -2
nixos/modules/services/x11/xserver.nix
···
};
services.xserver.displayManager.xserverArgs =
-
[ "-ac"
-
"-terminate"
+
[ "-terminate"
"-config ${configFile}"
"-xkbdir" "${cfg.xkbDir}"
] ++ optional (cfg.display != null) ":${toString cfg.display}"