Generate default constructor also for private classes when all parameters have default values

#KT-14408 Fixed

compiler/testData/codegen/box/jvmOverloads/privateClass.kt

@@ -0,0 +1,10 @@
+// IGNORE_BACKEND: JS
+
+// WITH_RUNTIME
+
+private data class C(val status: String = "OK")
+
+fun box(): String {
+    val c = (C::class.java.getConstructor().newInstance())
+    return c.status
+}