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/Storage/ATA/ATADevice.h

@@ -38,7 +38,7 @@ public:
 protected:
     ATADevice(ATAController const&, Address, MinorNumber, u16, u16, u64, NonnullOwnPtr<KString>);
 
-    WeakPtr<ATAController> m_controller;
+    LockWeakPtr<ATAController> m_controller;
     const Address m_ata_address;
     const u16 m_capabilities;
 };