IVGCVSW-2037 : separate registry for layer support intrefaces

* because their lifetime is different from backends

Change-Id: I9ba525e7e503b148cde1294933f3954b8bad3d68
diff --git a/src/backends/cl/ClBackendId.hpp b/src/backends/cl/ClBackendId.hpp
new file mode 100644
index 0000000..3f8fec2
--- /dev/null
+++ b/src/backends/cl/ClBackendId.hpp
@@ -0,0 +1,12 @@
+//
+// Copyright © 2017 Arm Ltd. All rights reserved.
+// SPDX-License-Identifier: MIT
+//
+#pragma once
+
+namespace armnn
+{
+
+constexpr const char * ClBackendId() { return "GpuAcc"; }
+
+} // namespace armnn