Move IOFile to a separate file

Reduces the number of files that need to be recompiled
when making changes to FileUtil.h.

Source/Core/Core/HW/Sram.cpp

@@ -5,7 +5,7 @@
 #include "Core/HW/Sram.h"
 
 #include "Common/CommonTypes.h"
-#include "Common/FileUtil.h"
+#include "Common/File.h"
 #include "Common/Logging/Log.h"
 #include "Common/Swap.h"
 #include "Core/ConfigManager.h"