COMPMID-3374: Remove memory state from  NEConcatenateLayer kernels

* Allow the following kernels to accept backing memory at run-time:
  * NEBatchConcatenateLayerKernel
  * NEDepthConcatenateLayerKernel
  * NEHeightConcatenateLayerKernel
  * NEWidthConcatenateLayerKernel
* Allow the following functions to accept backing memory at run-time:
  * NEConcatenateLayer

Signed-off-by: Georgios Pinitas <georgios.pinitas@arm.com>
Change-Id: Ib0b6714cff7f06a52dc74d294bc3e0d72a1c2419
Reviewed-on: https://review.mlplatform.org/c/ml/ComputeLibrary/+/3569
Tested-by: Arm Jenkins <bsgcomp@arm.com>
Reviewed-by: Michalis Spyrou <michalis.spyrou@arm.com>
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>
diff --git a/src/graph/backends/NEON/NEFunctionFactory.cpp b/src/graph/backends/NEON/NEFunctionFactory.cpp
index 2f31308..4fee630 100644
--- a/src/graph/backends/NEON/NEFunctionFactory.cpp
+++ b/src/graph/backends/NEON/NEFunctionFactory.cpp
@@ -47,6 +47,7 @@
 struct NETargetInfo
 {
     using TensorType         = arm_compute::ITensor;
+    using SrcTensorType      = const arm_compute::ITensor;
     using TensorConcreteType = arm_compute::Tensor;
     static Target TargetType;
 };