COMPMID-418 Add check and fix comments after preprocessor conditions

Change-Id: I1353fd652ee180e3931e58b4ce13d651a48c7e2c
Reviewed-on: http://mpd-gerrit.cambridge.arm.com/79567
Tested-by: Kaizen <jeremy.johnson+kaizengerrit@arm.com>
Reviewed-by: Moritz Pflanzer <moritz.pflanzer@arm.com>
diff --git a/tests/validation/Reference.h b/tests/validation/Reference.h
index ebd5fa7..cbdeb01 100644
--- a/tests/validation/Reference.h
+++ b/tests/validation/Reference.h
@@ -370,4 +370,4 @@
 } // namespace validation
 } // namespace test
 } // namespace arm_compute
-#endif
+#endif /* __ARM_COMPUTE_TEST_REFERENCE_REFERENCE_H__ */