This is something I'd expect in a science fiction novel, not the real world, but I'm not knocking the idea at all, I think it's rather brilliant, in fact.
However: Serious technical challenges, here. In development, they'd have to find some way to simulate the Martian atmosphere; can be done. Martian gravity? Not sure how you'd do that, but let's put it aside for now. 'Autonomous' is putting it mildly! This would have to be a bit more than your garden-variety quadcopter drone. I believe we have the technology for a system to map the ground below it with high enough resolution to allow it to find flat, level ground to land on (laser and/or radar?). I'll assume there are winds of some sort on Mars like there would be on any other planet that has an atmosphere, and we've had enough probes there to know what those winds are like (on the surface, at least). Run-time during flight would be a potential problem, although the gravity on Mars is less than that of Earth so it would take less energy to fly, right? Maybe a combination of an on-board nuclear power source like used on long-range space probes, plus batteries and solar? Unused power generated from the nuclear source and solar together recharge the batteries, wasting little. Of course what I don't know here is what a nuclear power sources' mass is, and would become very relevant for something that is going to fly; have to look that up later. How about disaster recovery? One bad landing, ending up upside down or on it's side, and it's all over unless there is a way to get it to right itself reliably. How about mode of flight? I'm thinking VTOL, which would allow it to conserve power by being able to operate in fixed-wing mode over longer distances, but there's the question of overall mass, and what would the wings have to look like in order to get sufficient lift in the Martian atmosphere?
A million questions! If they did this, I'd love to be a fly-on-the-wall (or a tech working on the project) during development and production of the probe.