hooklib: Add D3D11 and DXGI graphics hooks

IDZ only supports D3D11 and Ongeki/Unity uses D3D11 by default.

This also includes a window hook and fullscreen fix for problematic
games (I am looking at you IDZ).

hooklib/gfx/dxgi.h

@@ -0,0 +1,7 @@
+#pragma once
+
+#include <windows.h>
+
+#include "hooklib/gfx/gfx.h"
+
+void gfx_dxgi_hook_init(const struct gfx_config *cfg, HINSTANCE self);