scope hei_includes.hpp for internal use

This file should not be included in any headers consumed by the user
application.

Signed-off-by: Zane Shelley <zshelle@us.ibm.com>
Change-Id: Ifc3ff2faa03b96c8a7ace2feb7132d74df24f5cc
diff --git a/src/register/hei_register.hpp b/src/register/hei_register.hpp
index ff630f3..23692e5 100644
--- a/src/register/hei_register.hpp
+++ b/src/register/hei_register.hpp
@@ -1,7 +1,7 @@
 #pragma once
 
 #include <hei_bit_string.hpp>
-#include <hei_includes.hpp>
+#include <util/hei_includes.hpp>
 
 namespace libhei
 {