IVGCVSW-4482 Remove boost::ignore_unused

!referencetests:229377

Signed-off-by: Jan Eilers <jan.eilers@arm.com>
Change-Id: Ia9b360b4a057fe7bbce5b268092627c09a0dba82
diff --git a/src/armnn/Network.cpp b/src/armnn/Network.cpp
index 50a7df6..3663727 100644
--- a/src/armnn/Network.cpp
+++ b/src/armnn/Network.cpp
@@ -22,6 +22,7 @@
 #include <armnn/TypesUtils.hpp>
 #include <armnn/BackendRegistry.hpp>
 #include <armnn/Logging.hpp>
+#include <armnn/utility/IgnoreUnused.hpp>
 
 #include <ProfilingService.hpp>
 
@@ -628,7 +629,7 @@
                                                             OutputSlot& slot,
                                                             TensorHandleFactoryRegistry& registry)
 {
-    boost::ignore_unused(backends, slot, registry);
+    IgnoreUnused(backends, slot, registry);
     return ITensorHandleFactory::DeferredFactoryId;
 }