GFSK mode CRCs are broken

[ryankurte]

I documented this on the semtech forum but, they seem to have removed the post and I can't quite bring myself to spend a day re-identifying the failure. If you need CRCs under GFSK mode I suggest you implement this at the application level.

(Heads up there are a couple of other situations under GFSK in which the packet engine will fail wrt. sync-words and the variable message length header, but, I also can't remember the cause anymore)