Fixing compilation conditionals

Author: Arlodotexe

components/LayoutTransformControl/src/LayoutTransformControl.cs

@@ -212,7 +212,9 @@ private Matrix GetTransformMatrix(Transform transform)
         }
 
         // Fall back to no-op transformation
-#if HAS_UNO
+#if WINUI3
+        return Microsoft.UI.Xaml.Media.Matrix.Identity;
+#elif WINUI2
         return Windows.UI.Xaml.Media.Matrix.Identity;
 #else
         return Matrix.Identity;