Now, someone can correct me if I'm wrong, but I would think that the term "Moor" as indicating a Black person has been out of common usage for some time in the UK - I live on the other side of the pond, so that's just a vague impression. The term itself is perhaps archaic and forgotten enough now that most people in a general audience would have no particular reaction to it. The question then would be whether you feel comfortable with any lyric that compares black and white skin-colour. There is always the remote possibility that someone somewhere will take you task for it, so it comes down to how much that remote possibility does or does not bother you.