Fix initialization of object's INSTANCE$ field

Call object's constructor in <clinit> and ignore the result, but in the first
line of <init> save the current "this" to INSTANCE$

 #KT-4516 Fixed
 #KT-4543 Fixed
 #KT-5291 Fixed
 #KT-5523 Fixed
 #KT-5582 Fixed

compiler/testData/codegen/box/objects/localFunctionInObjectInitializer_kt4516.kt

@@ -0,0 +1,18 @@
+import java.util.HashMap
+
+object O {
+    val mmmap = HashMap<String, Int>();
+
+    {
+        fun doStuff() {
+            mmmap.put("two", 2)
+        }
+        doStuff()
+    }
+}
+
+fun box(): String {
+    val r = O.mmmap["two"]
+    if (r != 2) return "Fail: $r"
+    return "OK"
+}