I guess it is more aptly called bigotry. I was thinking along the lines of cloneship being a physical property of someone that's inherent to how they're produced (like how a newborn is probably going to be Black if its parents are Black) but the more I think about that the more it doesn't really apply because clones can really be any race.
People use 'racism' to mean 'bigotry' in general these days. Whether you accept this or not depends on your stance on prescriptivism vs. descriptivism.