Sorry but that doesn't have sense, every game could be better on next hardware, so whats the point!?
You have some people who buys Nintendo console in the first place for Zelda games, so in that case they buy Wii U for no reason!?
But I think there is no chance that Zelda wont come on Wii U.
Also even if Zelda will be on NX, it will probably be simple port not remaster or better version.