IVGCVSW-4210 Create a public API for the common backend files

 * Create a public API for the common backend files
 * Move OutputHandler to armnn internal
 * Remove unused headers

Signed-off-by: Matteo Martincigh <matteo.martincigh@arm.com>
Signed-off-by: Narumol Prangnawarat <narumol.prangnawarat@arm.com>
Change-Id: I3e86d908b021e3561befa9d45158d87d2cbb18c0
diff --git a/src/backends/backendsCommon/MemSyncWorkload.cpp b/src/backends/backendsCommon/MemSyncWorkload.cpp
index a1d309c..1c850db 100644
--- a/src/backends/backendsCommon/MemSyncWorkload.cpp
+++ b/src/backends/backendsCommon/MemSyncWorkload.cpp
@@ -3,12 +3,11 @@
 // SPDX-License-Identifier: MIT
 //
 
-#include "MemSyncWorkload.hpp"
-
-#include "CpuTensorHandle.hpp"
-
 #include <ResolveType.hpp>
 
+#include <backendsCommon/MemSyncWorkload.hpp>
+#include <backendsCommon/CpuTensorHandle.hpp>
+
 #include <boost/cast.hpp>
 
 #include <cstring>