Kernel: Make self-contained locking smart pointers their own classes

Until now, our kernel has reimplemented a number of AK classes to
provide automatic internal locking:

- RefPtr
- NonnullRefPtr
- WeakPtr
- Weakable

This patch renames the Kernel classes so that they can coexist with
the original AK classes:

- RefPtr => LockRefPtr
- NonnullRefPtr => NonnullLockRefPtr
- WeakPtr => LockWeakPtr
- Weakable => LockWeakable

The goal here is to eventually get rid of the Lock* classes in favor of
using external locking.

Kernel/Bus/USB/USBController.h

@@ -31,7 +31,7 @@ public:
 private:
     u8 m_next_device_index { 1 };
 
-    IntrusiveListNode<USBController, NonnullRefPtr<USBController>> m_controller_list_node;
+    IntrusiveListNode<USBController, NonnullLockRefPtr<USBController>> m_controller_list_node;
 
 public:
     using List = IntrusiveList<&USBController::m_controller_list_node>;