Description of changes

xorg: remove xlibsWrapper attribute, use top-level one instead

I noticed this attribute when tried to override xorg scope via
overlay:

final: prev {
  xorg = prev.xorg.overrideScope' (f: p: {
    libXfont2 = p.libXfont2.overrideAttrs (oa: {
      patches = (oa.patches or []) ++ [
        ../libXfont2/nofollow.patch
      ];
    });
  }) // { inherit (prev) xlibsWrapper; };
}

As a result I got unexpected pulseaudio build failures:

$ nix build --no-link -f. pulseaudio
error: attribute 'xlibsWrapper' missing

       at pkgs/servers/pulseaudio/default.nix:79:37:

           78|       ++ lib.optional jackaudioSupport libjack2
           79|       ++ lib.optionals x11Support [ xorg.xlibsWrapper xorg.libXtst xorg.libXi ]
             |                                     ^
           80|       ++ lib.optional useSystemd systemd

Previous changes in this branch remove references to xorg.xlibsWrapper
in favour of xlibsWrapper. Let's remove injection of this attribute into
`xorg.

Things done

• Built on platform(s)
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• For non-Linux: Is sandbox = true set in nix.conf? (See Nix manual)
• Tested, as applicable:
  • NixOS test(s) (look inside nixos/tests)
  • and/or package tests
  • or, for functions and "core" functionality, tests in lib/tests or pkgs/test
  • made sure NixOS tests are linked to the relevant packages
• Tested compilation of all packages that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review rev HEAD". Note: all changes have to be committed, also see nixpkgs-review usage
• Tested basic functionality of all binary files (usually in ./result/bin/)
• 22.11 Release Notes (or backporting 22.05 Release notes)
  • (Package updates) Added a release notes entry if the change is major or breaking
  • (Module updates) Added a release notes entry if the change is significant
  • (Module addition) Added a release notes entry if adding a new NixOS module
  • (Release notes changes) Ran nixos/doc/manual/md-to-db.sh to update generated release notes
• Fits CONTRIBUTING.md.