COMPMID-2826 Comply with DCL51-CPP

Rename all header guards to be compliant with DCL51-CPP

Change-Id: I47b09375bb1b8d39d80c275ce69a3f25fb385d75
Signed-off-by: Michalis Spyrou <micspy01@e123758.cambridge.arm.com>
Reviewed-on: https://review.mlplatform.org/c/2393
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>
Reviewed-by: Michele Di Giorgio <michele.digiorgio@arm.com>
Tested-by: Arm Jenkins <bsgcomp@arm.com>
diff --git a/arm_compute/core/CL/kernels/CLWidthConcatenate4TensorsKernel.h b/arm_compute/core/CL/kernels/CLWidthConcatenate4TensorsKernel.h
index 952fd99..d391b22 100644
--- a/arm_compute/core/CL/kernels/CLWidthConcatenate4TensorsKernel.h
+++ b/arm_compute/core/CL/kernels/CLWidthConcatenate4TensorsKernel.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018 ARM Limited.
+ * Copyright (c) 2018-2019 ARM Limited.
  *
  * SPDX-License-Identifier: MIT
  *
@@ -22,8 +22,8 @@
  * SOFTWARE.
  */
 
-#ifndef __ARM_COMPUTE_CLWIDTHCONCATENATE_4TENSORS_KERNEL_H__
-#define __ARM_COMPUTE_CLWIDTHCONCATENATE_4TENSORS_KERNEL_H__
+#ifndef ARM_COMPUTE_CLWIDTHCONCATENATE_4TENSORS_KERNEL_H
+#define ARM_COMPUTE_CLWIDTHCONCATENATE_4TENSORS_KERNEL_H
 
 #include "arm_compute/core/CL/ICLKernel.h"
 #include "arm_compute/core/Types.h"
@@ -82,4 +82,4 @@
     ICLTensor       *_output;
 };
 } // namespace arm_compute
-#endif /* __ARM_COMPUTE_CLWIDTHCONCATENATE_4TENSORS_KERNEL_H__ */
+#endif /* ARM_COMPUTE_CLWIDTHCONCATENATE_4TENSORS_KERNEL_H */