Extension properties in class: don't put receiver on stack for GETFIELD/PUTFIELD instruction

#KT-3031 Fixed

compiler/testData/codegen/extensionProperties/inClassWithGetter.kt

@@ -0,0 +1,15 @@
+class Test {
+  val Int.foo: String = "OK"
+    get() {
+        val a = $foo
+        return "OK"
+    }
+
+  fun test(): String {
+     return 1.foo
+  }
+}
+
+fun box(): String {
+   return Test().test()
+}