COMPMID-1761: NEON: Implement Pack

Change-Id: Icc3392494b1e3361e8fd925da200827c494351b3
Reviewed-on: https://review.mlplatform.org/430
Reviewed-by: Manuel Bottini <manuel.bottini@arm.com>
Tested-by: Arm Jenkins <bsgcomp@arm.com>
Reviewed-by: Giuseppe Rossini <giuseppe.rossini@arm.com>
Reviewed-by: Gian Marco Iodice <gianmarco.iodice@arm.com>
diff --git a/arm_compute/runtime/CL/functions/CLStackLayer.h b/arm_compute/runtime/CL/functions/CLStackLayer.h
index 9794014..5b821b8 100644
--- a/arm_compute/runtime/CL/functions/CLStackLayer.h
+++ b/arm_compute/runtime/CL/functions/CLStackLayer.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018 ARM Limited.
+ * Copyright (c) 2018-2019 ARM Limited.
  *
  * SPDX-License-Identifier: MIT
  *
@@ -48,13 +48,17 @@
     CLStackLayer();
     /** Initialise the kernel's inputs vector and output.
      *
+     * @note Supported input tensor rank: up to 4
+     *
      * @param[in]  input  The vectors containing all the tensors with the same shape to stack. Data types supported: U8/S8/QASYMM8/U16/S16/F16/U32/S32/F32
      * @param[in]  axis   The dimension to stack the tensors along. It must be smaller than the number of input dimensions.
      *                    Negative values wrap around
      * @param[out] output Output tensor. Data types supported: Same as @p input.
      */
     void configure(const std::vector<ICLTensor *> &input, int axis, ICLTensor *output);
-    /** Static function to check if given info will lead to a valid configuration of @ref CLDepthConcatenateLayer
+    /** Static function to check if given info will lead to a valid configuration of @ref CLStackLayerKernel
+     *
+     * @note Supported input tensor rank: up to 4
      *
      * @param[in] input  The vectors containing all the tensors info with the same shape to stack. Data types supported: U8/S8/QASYMM8/U16/S16/F16/U32/S32/F32
      * @param[in] axis   The dimension to stack the tensors along. It must be smaller than the number of input dimensions.
@@ -73,5 +77,5 @@
     std::unique_ptr<CLStackLayerKernel[]> _stack_kernels;
     unsigned int                          _num_inputs;
 };
-}
+} // namespace arm_compute
 #endif /* __ARM_COMPUTE_CLSTACKLAYER_H__ */