nixos/gdm: don't set XCURSOR_PATH

nixos/modules/services/x11/display-managers/gdm.nix

@@ -142,8 +142,6 @@ in
           GDM_X_SERVER_EXTRA_ARGS = toString
             (filter (arg: arg != "-terminate") cfg.xserverArgs);
           XDG_DATA_DIRS = "${cfg.session.desktops}/share/";
-          # Find the mouse
-          XCURSOR_PATH = "~/.icons:${pkgs.gnome3.adwaita-icon-theme}/share/icons";
         } // optionalAttrs (xSessionWrapper != null) {
           # Make GDM use this wrapper before running the session, which runs the
           # configured setupCommands. This relies on a patched GDM which supports