IVGCVSW-3030 Add a mock backend for unit testing

 * Added a mock implementation of an ArmNN backend for unit
   testing
 * Implemented a mock version of OptimizeSubgraphView
 * Fixed a typo in the Optimization API

Change-Id: Ic7acf7cc5c2a76a918e94cdc356baae7c7597a6d
Signed-off-by: Matteo Martincigh <matteo.martincigh@arm.com>
diff --git a/src/backends/backendsCommon/OptimizationViews.hpp b/src/backends/backendsCommon/OptimizationViews.hpp
index e96c11a..a63fdf1 100644
--- a/src/backends/backendsCommon/OptimizationViews.hpp
+++ b/src/backends/backendsCommon/OptimizationViews.hpp
@@ -30,7 +30,7 @@
     using Subgraphs = std::vector<SubgraphView>;
     using Substitutions = std::vector<SubstitutionPair>;
 
-    void AddSubstituion(SubstitutionPair&& substitution)
+    void AddSubstitution(SubstitutionPair&& substitution)
     {
         m_SuccesfulOptimizations.emplace_back(substitution);
     }