Generate private constructor for object

#KT-9510 Fixed

compiler/testData/codegen/box/privateConstructors/captured.kt

@@ -0,0 +1,10 @@
+public open class Outer private constructor(val s: String) {
+
+    companion object {
+        fun test () =  { Outer("OK") }()
+    }
+}
+
+fun box(): String {
+    return Outer.test().s
+}