COMPMID-589: Refactor HOGDescriptor validation test

Change-Id: Iee93f17a8ce303cff878b1c5d8904947fb910838
Reviewed-on: https://eu-gerrit-1.euhpc.arm.com/118892
Tested-by: Jenkins <bsgcomp@arm.com>
Reviewed-by: Anthony Barbier <anthony.barbier@arm.com>
diff --git a/tests/validation/CL/HOGDescriptor.cpp b/tests/validation/CL/HOGDescriptor.cpp
index aef265a..f5a00ba 100644
--- a/tests/validation/CL/HOGDescriptor.cpp
+++ b/tests/validation/CL/HOGDescriptor.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017, 2018 ARM Limited.
+ * Copyright (c) 2017-2018 ARM Limited.
  *
  * SPDX-License-Identifier: MIT
  *
@@ -44,7 +44,7 @@
 {
 namespace
 {
-AbsoluteTolerance<float> tolerance(1e-2f);
+RelativeTolerance<float> tolerance(0.001f);
 } // namespace
 
 TEST_SUITE(CL)