Add missing support aomenc parameter for aom-qm
Add missing support aomenc parameter for aom-qm

BUG=aomedia:79

Change-Id: I09c9547295e4ab540861d6d4def24718dcefc854

smarter/aom,mbebenita/aom,smarter/aom,smarter/aom,smarter/aom,mbebenita/aom,mbebenita/aom,mbebenita/aom,mbebenita/aom,GrokImageCompression/aom,GrokImageCompression/aom,mbebenita/aom,GrokImageCompression/aom,luctrudeau/aom,GrokImageCompression/aom,luctrudeau/aom,smarter/aom,mbebenita/aom,luctrudeau/aom,mbebenita/aom,luctrudeau/aom,GrokImageCompression/aom,luctrudeau/aom,mbebenita/aom,GrokImageCompression/aom,luctrudeau/aom,smarter/aom