Fix isInitialized for companion lateinit properties

Instead of trying to access a missing field `Foo.foo`, call the
synthetic accessor `Foo.access$getFoo$cp` which, as per previous commit,
no longer contains the lateinit assertion

 #KT-21862 Fixed

compiler/tests/org/jetbrains/kotlin/codegen/BlackBoxCodegenTestGenerated.java

@@ -17860,6 +17860,11 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
                     KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("compiler/testData/codegen/box/properties/lateinit/isInitializedAndDeinitialize"), Pattern.compile("^(.+)\\.kt$"), TargetBackend.JVM, true);
                 }
 
+                @TestMetadata("companionObjectField.kt")
+                public void testCompanionObjectField() throws Exception {
+                    runTest("compiler/testData/codegen/box/properties/lateinit/isInitializedAndDeinitialize/companionObjectField.kt");
+                }
+
                 @TestMetadata("emptyLhs.kt")
                 public void testEmptyLhs() throws Exception {
                     runTest("compiler/testData/codegen/box/properties/lateinit/isInitializedAndDeinitialize/emptyLhs.kt");