Turn off incorrect switch-optimization for when by enums

#KT-24708 Fixed

compiler/testData/codegen/bytecodeText/whenEnumOptimization/differentEnumClasses2.kt

@@ -0,0 +1,19 @@
+enum class A {
+    OK
+}
+
+enum class B {
+    FAIL
+}
+
+fun f() = A.OK
+
+fun box(): String {
+    return when (f()) {
+        B.FAIL -> "fail"
+        A.OK -> "OK"
+    }
+}
+
+// 0 TABLESWITCH
+// 0 LOOKUPSWITCH