Remove usage of valid window region in NHWC CPU kernels - Part2

Remove set_valid_region methods from all NHWC CPU ML functions /
operators / kernels

Resolves COMPMID-4152 (2/2)

Change-Id: If9725e9c5b0213b87db96675e81b7fb724970b98
Signed-off-by: SiCongLi <sicong.li@arm.com>
Reviewed-on: https://review.mlplatform.org/c/ml/ComputeLibrary/+/5203
Reviewed-by: Georgios Pinitas <georgios.pinitas@arm.com>
Tested-by: Arm Jenkins <bsgcomp@arm.com>
diff --git a/src/core/NEON/kernels/NEBoundingBoxTransformKernel.cpp b/src/core/NEON/kernels/NEBoundingBoxTransformKernel.cpp
index 03d6e1c..9662203 100644
--- a/src/core/NEON/kernels/NEBoundingBoxTransformKernel.cpp
+++ b/src/core/NEON/kernels/NEBoundingBoxTransformKernel.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019-2020 Arm Limited.
+ * Copyright (c) 2019-2021 Arm Limited.
  *
  * SPDX-License-Identifier: MIT
  *
@@ -101,9 +101,6 @@
 
     const unsigned int num_boxes = boxes->info()->dimension(1);
     Window             win       = calculate_max_window(*pred_boxes->info(), Steps());
-    Coordinates        coord;
-    coord.set_num_dimensions(pred_boxes->info()->num_dimensions());
-    pred_boxes->info()->set_valid_region(ValidRegion(coord, pred_boxes->info()->tensor_shape()));
     win.set(Window::DimX, Window::Dimension(0, 1u));
     win.set(Window::DimY, Window::Dimension(0, num_boxes));