build(flake): Switch to nixpkgs's wrapped mold linker

By now a wrapped version of mold exists, which thus works with the
NixOS libraries. This is obviously the same as my self-wrapped version,
but vendoring is just not important here.

flake.nix

@@ -37,28 +37,6 @@
     ...
   }:
     flake-utils.lib.eachDefaultSystem (system: let
-      inherit (pkgs) lib;
-      bintools-wrapper = "${nixpkgs}/pkgs/build-support/bintools-wrapper";
-      mold' = pkgs.symlinkJoin {
-        name = "mold";
-        paths = [pkgs.mold];
-        nativeBuildInputs = [pkgs.makeWrapper];
-        suffixSalt = lib.replaceStrings ["-" "."] ["_" "_"] pkgs.targetPlatform.config;
-        postBuild = ''
-          for bin in ${pkgs.mold}/bin/*; do
-            rm $out/bin/"$(basename "$bin")"
-
-            export prog="$bin"
-            substituteAll "${bintools-wrapper}/ld-wrapper.sh" $out/bin/"$(basename "$bin")"
-            chmod +x $out/bin/"$(basename "$bin")"
-
-            mkdir -p $out/nix-support
-            substituteAll "${bintools-wrapper}/add-flags.sh" $out/nix-support/add-flags.sh
-            substituteAll "${bintools-wrapper}/add-hardening.sh" $out/nix-support/add-hardening.sh
-            substituteAll "${bintools-wrapper}/../wrapper-common/utils.bash" $out/nix-support/utils.bash
-          done
-        '';
-      };
       pkgs = import nixpkgs {
         inherit system;
         overlays = [(import rust-overlay)];
@@ -79,7 +57,7 @@
 
       nativeBuildInputs = with pkgs; [
         pkg-config
-        mold'
+        mold-wrapped
       ];
       buildInputs = with pkgs; [
         openssl