IVGCVSW-4449 Add QLstm ref implementation

* Adds ref implemenation for new HAL 1.3
  operator, QLstm.
* Adds Layer and CreateWorkload unit tests.
* Adds WorkloadData validate for QLstm.

Signed-off-by: James Conroy <james.conroy@arm.com>
Change-Id: I8a721f07ff06105e6495a1a0561b9503aa8146dc
diff --git a/src/backends/reference/RefLayerSupport.cpp b/src/backends/reference/RefLayerSupport.cpp
index 87d2921..034cd12 100644
--- a/src/backends/reference/RefLayerSupport.cpp
+++ b/src/backends/reference/RefLayerSupport.cpp
@@ -1573,6 +1573,30 @@
     return supported;
 }
 
+bool RefLayerSupport::IsQLstmSupported(const TensorInfo& input,
+                                       const TensorInfo& previousOutputIn,
+                                       const TensorInfo& previousCellStateIn,
+                                       const TensorInfo& outputStateOut,
+                                       const TensorInfo& cellStateOut,
+                                       const TensorInfo& output,
+                                       const QLstmDescriptor& descriptor,
+                                       const LstmInputParamsInfo& paramsInfo,
+                                       Optional<std::string&> reasonIfUnsupported) const
+{
+    IgnoreUnused(input);
+    IgnoreUnused(previousOutputIn);
+    IgnoreUnused(previousCellStateIn);
+    IgnoreUnused(outputStateOut);
+    IgnoreUnused(cellStateOut);
+    IgnoreUnused(output);
+    IgnoreUnused(descriptor);
+    IgnoreUnused(paramsInfo);
+
+    IgnoreUnused(reasonIfUnsupported);
+
+    return true;
+}
+
 bool RefLayerSupport::IsQuantizeSupported(const TensorInfo& input,
                                           const TensorInfo& output,
                                           Optional<std::string&> reasonIfUnsupported) const