Reduce unneeded abs() call in level map
Reduce unneeded abs() call in level map

Change-Id: I727f1750b95a385a5497fe9b0885da52e8b06743

GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom,GrokImageCompression/aom