Kernel: Require lock rank for Spinlock construction

All users which relied on the default constructor use a None lock rank
for now. This will make it easier to in the future remove LockRank and
actually annotate the ranks by searching for None.

Kernel/Graphics/VirtIOGPU/GraphicsAdapter.h

@@ -124,7 +124,7 @@ private:
 
     // Synchronous commands
     WaitQueue m_outstanding_request;
-    Spinlock m_operation_lock;
+    Spinlock m_operation_lock { LockRank::None };
     NonnullOwnPtr<Memory::Region> m_scratch_space;
 };
 }