IVGCVSW-2056 + IVGCVSW-2064 : move ClContextControl to the ClBackend

Change-Id: Ice19d3f763298bc14585267df389e99df846320d
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 257a49d..b33d4b6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -154,6 +154,7 @@
     include/armnn/ILayerSupport.hpp
     include/armnn/INetwork.hpp
     include/armnn/IProfiler.hpp
+    include/armnn/IBackend.hpp
     include/armnn/IRuntime.hpp
     include/armnn/LayerSupport.hpp
     include/armnn/LstmParams.hpp