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/src/core/CL/cl_kernels/depth_convert.cl b/src/core/CL/cl_kernels/depth_convert.cl
index c8eaa95..3a1c7ca 100644
--- a/src/core/CL/cl_kernels/depth_convert.cl
+++ b/src/core/CL/cl_kernels/depth_convert.cl
@@ -25,9 +25,9 @@
 
 #ifdef SATURATE
 #define CONVERT_DOWN(x, type) CONVERT_SAT(x, type)
-#else
+#else /* SATURATE */
 #define CONVERT_DOWN(x, type) CONVERT(x, type)
-#endif
+#endif /* SATURATE */
 
 /** This function performs a down-scaling depth conversion.
  *