Fixed macro redefinition in Half.hpp

* Fixed the compiler warnings about macro redefinitions when building the driver

* Resolves MLCE-622

Change-Id: I7231f9772dc0f38191853ff378670d45648ef7f6
Signed-off-by: Pablo Tello <pablo.tello@arm.com>
diff --git a/src/armnnUtils/Half.hpp b/src/armnnUtils/Half.hpp
index 573d5c2..d55c2f9 100644
--- a/src/armnnUtils/Half.hpp
+++ b/src/armnnUtils/Half.hpp
@@ -5,11 +5,13 @@
 
 #pragma once
 
+#include <type_traits>
+
 // Set style to round to nearest
 #define HALF_ROUND_STYLE 1
+#define HALF_ROUND_TIES_TO_EVEN 1
 
-#include <type_traits>
-#include <half/half.hpp>
+#include "half/half.hpp"
 
 namespace armnn
 {
@@ -35,4 +37,4 @@
     : integral_constant< bool, true >
 {};
 
-} //namespace std
\ No newline at end of file
+} //namespace std