I don't think they would use the same chipset.
Nintendo has lots of problems with the Wii U chip. It's expensive because they're basically using an ancient IBM part that they can't do a die shrink on so that's stuck on 40nm.
The Renesas embedded RAM they use on the system is also a problem because there's only one factory that makes it, and Sony owns it and will eventually phase out production of it.
Nintendo is likely dying to get out from under the Wii U's ugly legacy, it's an expensive piece of hardware because of bad design decisions and forced Wii backwards compatibility.
If they do want to go the "cheap console" route they can do so today with much better options than what the Wii U chip offers, not only for cost but performance too.
Imagination (PowerVR) and ARM + AMD can both likely give Nintendo a chip for cheaper than what they're paying for the Wii U that is much more powerful and even much more power efficient.
