[K/N] Move kotlin.native.internal.Debugging into kotlin.native.runtime

As a part of efforts to stabilize Native stdlib #KT-55765.

kotlin-native/backend.native/tests/produce_dynamic/unhandledException/unhandled.kt

@@ -2,10 +2,11 @@
  * Copyright 2010-2021 JetBrains s.r.o. and Kotlin Programming Language contributors.
  * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
  */
-@file:OptIn(FreezingIsDeprecated::class, ExperimentalStdlibApi::class)
+@file:OptIn(FreezingIsDeprecated::class, ExperimentalStdlibApi::class, kotlin.native.runtime.NativeRuntimeApi::class)
 
 import kotlin.native.concurrent.*
 import kotlin.native.internal.*
+import kotlin.native.runtime.Debugging
 
 fun setHookAndThrow() {
     val hook = { throwable: Throwable ->