kdePackages.kwayland-integration: fix build, use in Plasma 6 (#435663)

nixos/modules/services/desktop-managers/plasma6.nix

···
       ++ lib.optionals config.services.desktopManager.plasma6.enableQt5Integration [
         breeze.qt5
         plasma-integration.qt5
-        pkgs.plasma5Packages.kwayland-integration
+        kwayland-integration
         (
           # Only symlink the KIO plugins, so we don't accidentally pull any services
           # like KCMs or kcookiejar

pkgs/kde/plasma/kwayland-integration/default.nix

···
-{ mkKdeDerivation }:
-mkKdeDerivation {
+{
+  stdenv,
+  sources,
+
+  cmake,
+  pkg-config,
+  libsForQt5,
+  wayland-scanner,
+
+  plasma-wayland-protocols,
+  wayland,
+  wayland-protocols,
+}:
+# not mkKdeDerivation because this is Qt5 land
+stdenv.mkDerivation rec {
   pname = "kwayland-integration";
-  # FIXME(qt5)
-  meta.broken = true;
+  inherit (sources.${pname}) version;
+
+  src = sources.${pname};
+
+  nativeBuildInputs = [
+    cmake
+    pkg-config
+    libsForQt5.extra-cmake-modules
+  ];
+
+  buildInputs = [
+    libsForQt5.qtbase
+    libsForQt5.qtwayland
+
+    libsForQt5.kwayland
+    libsForQt5.kwindowsystem
+
+    plasma-wayland-protocols
+    wayland
+    wayland-protocols
+    wayland-scanner
+  ];
+
+  dontWrapQtApps = true;
 }