kf6-kwindowsystem: disable Wayland platform plugin (greeter milestone)

KWINDOWSYSTEM_WAYLAND=ON pulled in an escalating chain — PlasmaWaylandProtocols,
xkbcommon, then the KWayland QML plugin links Qt6::GuiPrivate and uses Qt private
Wayland APIs likely to need further Redox porting. The SDDM greeter is a
fullscreen client that links the core KWindowSystem library, not this plugin, so
set KWINDOWSYSTEM_WAYLAND=OFF to unblock the greeter build (matches the recipe/s
original "Wayland disabled" intent) and drop the plugin-only deps. Re-enable +
port Qt6::GuiPrivate usage when wiring the full Plasma desktop.

local/recipes/kde/kf6-kwindowsystem/recipe.toml

@@ -15,15 +15,11 @@ dependencies = [
     # find_package(Qt6Qml) via ECMQmlModule. Qt6Qml comes from qtdeclarative, so
     # it must be a dependency or configure fails "Could not find ... Qt6Qml".
     "qtdeclarative",
-    # KWINDOWSYSTEM_WAYLAND=ON requires Qt6WaylandClient (qtwayland),
-    # WaylandProtocols (wayland-protocols) and PlasmaWaylandProtocols
-    # (plasma-wayland-protocols). Declare all three so configure's
-    # find_package(... REQUIRED) resolves from this recipe's sysroot.
-    "qtwayland",
-    "wayland-protocols",
-    "plasma-wayland-protocols",
-    # src/platforms/wayland/CMakeLists.txt: pkg_check_modules(xkbcommon REQUIRED)
-    "libxkbcommon",
+    # NOTE: KWINDOWSYSTEM_WAYLAND is disabled below (greeter milestone) so the
+    # Wayland platform plugin's deps (qtwayland/wayland-protocols/
+    # plasma-wayland-protocols/libxkbcommon) and its Qt6::GuiPrivate private-API
+    # usage are not pulled in. Re-add them when re-enabling Wayland for the full
+    # desktop (see the KWINDOWSYSTEM_WAYLAND=OFF note in the cmake args).
     "kf6-extra-cmake-modules",
 ]
 script = """
@@ -54,7 +50,7 @@ cmake "${COOKBOOK_SOURCE}" \
     -DBUILD_QCH=OFF \
     -DKWINDOWSYSTEM_QML=ON \
     -DKWINDOWSYSTEM_X11=OFF \
-    -DKWINDOWSYSTEM_WAYLAND=ON \
+    -DKWINDOWSYSTEM_WAYLAND=OFF \
     -Wno-dev
 
 cmake --build . -j${COOKBOOK_MAKE_JOBS}