Support inline functions inside inline classes

compiler/testData/codegen/box/inlineClasses/inlineFunctionInsideInlineClass.kt

@@ -0,0 +1,14 @@
+// !LANGUAGE: +InlineClasses
+
+inline class Foo(val x: Int) {
+    inline fun inc(): Foo = Foo(x + 1)
+}
+
+fun box(): String {
+    val a = Foo(0)
+    val b = a.inc().inc()
+
+    if (b.x != 2) return "fail"
+
+    return "OK"
+}