MLCE-110 Propagate error from armnn EnqueueWorkload

Change-Id: Ic53b1cdbdd3a7d656932651c74911940affc09b6
Signed-off-by: Matthew Bentham <matthew.bentham@arm.com>
diff --git a/ArmnnPreparedModel.hpp b/ArmnnPreparedModel.hpp
index 3c4b32b..f6008b8 100644
--- a/ArmnnPreparedModel.hpp
+++ b/ArmnnPreparedModel.hpp
@@ -42,7 +42,8 @@
                       const ::android::sp<IExecutionCallback>& callback);
 
     /// Executes this model with dummy inputs (e.g. all zeroes).
-    void ExecuteWithDummyInputs();
+    /// \return false on failure, otherwise true
+    bool ExecuteWithDummyInputs();
 
 private:
     template <typename TensorBindingCollection>