[FIR2IR] Don't add synthetic propertiy fake overrides to parent class

This fixes a KMP issue where IrActualizer would add duplicate
fake overrides because the parent class would have both the getter
and the synthetic property in its list of declarations.
Now, the synthetic property fake overrides are still generated and
cached in the Fir2IrDeclarationStorage, but not added to the class.

#KT-60854 Fixed

compiler/tests-gen/org/jetbrains/kotlin/codegen/LightAnalysisModeTestGenerated.java

@@ -28466,6 +28466,11 @@ public class LightAnalysisModeTestGenerated extends AbstractLightAnalysisModeTes
             runTest("compiler/testData/codegen/box/multiplatform/kt59613.kt");
         }
 
+        @TestMetadata("kt60854.kt")
+        public void testKt60854() throws Exception {
+            runTest("compiler/testData/codegen/box/multiplatform/kt60854.kt");
+        }
+
         @TestMetadata("noArgActualConstructor.kt")
         public void testNoArgActualConstructor() throws Exception {
             runTest("compiler/testData/codegen/box/multiplatform/noArgActualConstructor.kt");