[NTOSKRNL] Implement write behind in Cc

[NTOSKRNL] Implement write behind in Cc

For now, this is just a split between scan and flush that
were both done during lazy scan previously.
Lazy scan shouldn't perform any write operation, but only
queue a write behind operation.

Our implementation is far from the original, as it seems
our lazy scan should queue a write behind operation per
shared cache map. Right now, we only perform global
operation.