Split libnu into libplatform, libamex

Going to add some ALLS stuff to libplatform and the ALLS hardware
does not contain an AMEX board.

amex/eeprom.h

@@ -0,0 +1,12 @@
+#pragma once
+
+#include <windows.h>
+
+DEFINE_GUID(
+        eeprom_guid,
+        0xB7970F0C,
+        0x31C4,
+        0x45FF,
+        0x96, 0x18, 0x0A, 0x24, 0x00, 0x94, 0xB2, 0x71);
+
+HRESULT eeprom_hook_init(void);