feat: DTB now populates VMBootMemoryMap structure.

Kernel/Include/VM/PMM.h

@@ -0,0 +1,19 @@
+#pragma once
+#include <Types.h>
+
+enum {
+    kVMPageSize = 4096,
+    kVMBlocksPerByte = 8,
+    kVMMaxReservedRegions = 128,
+};
+
+typedef struct {
+    UInt64 base;
+    Size size;
+} VMMemoryRegion;
+
+typedef struct {
+    VMMemoryRegion totalRAM;
+    VMMemoryRegion reserved[kVMMaxReservedRegions];
+    UInt32 reservedCount;
+} VMBootMemoryMap;