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/runtime/CL/functions/CLGEMMLowpOutputStage.h b/arm_compute/runtime/CL/functions/CLGEMMLowpOutputStage.h
index 25fa142..f453879 100644
--- a/arm_compute/runtime/CL/functions/CLGEMMLowpOutputStage.h
+++ b/arm_compute/runtime/CL/functions/CLGEMMLowpOutputStage.h
@@ -308,4 +308,4 @@
     static Status validate(const ITensorInfo *input, const ITensorInfo *bias, const ITensorInfo *output, int min = 0, int max = 0);
 };
 } // namespace arm_compute
-#endif /*__ARM_COMPUTE_CLGEMMLOWPOUTPUTSTAGE_H__ */
\ No newline at end of file
+#endif /*ARM_COMPUTE_CLGEMMLOWPOUTPUTSTAGE_H */
\ No newline at end of file