qtutilities: add Qt6 support

pkgs/development/libraries/qtutilities/default.nix

@@ -28,6 +28,7 @@ stdenv.mkDerivation (finalAttrs: {
   ];
 
   cmakeFlags = [
+    "-DQT_PACKAGE_PREFIX=Qt${lib.versions.major qtbase.version}"
     "-DBUILD_SHARED_LIBS=ON"
   ];
 

pkgs/top-level/qt6-packages.nix

@@ -60,6 +60,8 @@ makeScopeWithSplicing' {
     qt5Kvantum = pkgs.libsForQt5.qtstyleplugin-kvantum;
   };
 
+  qtutilities = callPackage ../development/libraries/qtutilities { };
+
   quazip = callPackage ../development/libraries/quazip { };
 
   qscintilla = callPackage ../development/libraries/qscintilla { };