zeusminer: Identify the Chip # both in the UI and RPC API

![ZeusMiner Stats](http://www.nwoolls.com/othercontent/BFGMiner%20ZeusMiner%20Per-Core-Chips-IDd.png)
https://github.com/luke-jr/bfgminer/blob/bfgminer/api.c#L1544 appears to be missing for the devdetails case. I'll fix that...