JVM IR: Fix enum constructor visibility

compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/EnumClassLowering.kt

@@ -109,7 +109,7 @@ private class EnumClassLowering(val context: JvmBackendContext) : ClassLoweringP
                 enumConstructor.origin,
                 IrConstructorSymbolImpl(descriptor),
                 enumConstructor.name,
-                Visibilities.PROTECTED,
+                Visibilities.PRIVATE,
                 returnType = enumConstructor.returnType,
                 isInline = enumConstructor.isInline,
                 isExternal = enumConstructor.isExternal,

compiler/testData/writeFlags/function/constructors/enum.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 enum class Foo {
     A, B, C
 }