[IR] add testdata for dumpKotlinLike

compiler/testData/ir/irText/singletons/enumEntry.kt.txt

@@ -0,0 +1,20 @@
+open enum class Z : Enum<Z> {
+  private constructor() /* primary */ {
+    TODO("IrEnumConstructorCall")
+        /* InstanceInitializerCall */
+
+  }
+
+  ENTRY init = TODO("IrEnumConstructorCall")
+
+
+
+
+
+
+  fun values(): Array<Z> /* Synthetic body for ENUM_VALUES */
+
+  fun valueOf(value: String): Z /* Synthetic body for ENUM_VALUEOF */
+
+}
+