However many the artist deems necessary.
I usually write songs without traditional structure -- remixes included. I have, for instance, an A, B, C, D and E among which some common elements are shared, but there's rarely a repeating section. Yes, I know it's a little weird to admit it, but I don't much enjoy traditional song structure. You've got creative license, so do whatever feels right to you.
That being said, writing something like A, B, A, C, B, D or what have you is much easier to fill time with, but is it appealing to you? Does it work in that particular mix? Would more original material be most appropriate?
I'm sure you weren't stabbing for an absolute answer, but this kind of decision is just totally situational and would be approached differently from person to person.