Kernel: Implement bare boness DMA Region

This does nothing but allocate contiguous physical and virtual memory
and map it as CacheDisable. Also memory is automatically freed RAII style.

kernel/include/kernel/Memory/DMARegion.h

@@ -0,0 +1,27 @@
+#pragma once
+
+#include <kernel/Memory/MemoryRegion.h>
+
+namespace Kernel
+{
+	
+	class DMARegion
+	{
+	public:
+		BAN::ErrorOr<BAN::UniqPtr<DMARegion>> create(size_t size);
+		~DMARegion();
+
+		size_t size() const { return m_size; }
+		vaddr_t vaddr() const { return m_vaddr; }
+		paddr_t paddr() const { return m_paddr; }
+
+	private:
+		DMARegion(size_t size, vaddr_t vaddr, paddr_t paddr);
+
+	private:
+		const size_t m_size;
+		const vaddr_t m_vaddr;
+		const paddr_t m_paddr;
+	};
+
+}