Remove OneShotInfo field of LFReEntrant
The field is only used in withNewTickyCounterFun and it's easier to directly pass a parameter for one-shot info to withNewTickyCounterFun instead of passing it via LFReEntrant. This also makes !2842 (closed) simpler.
@simonpj please review. This effectively makes the change I describe here -- so one-shot info of a LFReEntrant is now one-shot info of its binder rather than its first argument. Let me know if this is not correct.
A second commit removes some unused stuff from Ticky.hs.