Only private constructors for sealed / enum classes #KT-12377 Fixed

Also #KT-8497 Fixed

compiler/testData/codegen/box/enum/publicConstructorWithDefault.kt

@@ -1,9 +0,0 @@
-// KT-8438 org.jetbrains.org.objectweb.asm.tree.analysis.AnalyzerException: Error at instruction 4: Cannot pop operand off an empty stack
-
-enum class E public constructor(x: String = "OK") {
-    ENTRY();
-
-    val result = x
-}
-
-fun box(): String = E.ENTRY.result