Turn FSM into a blackbox, much like PSM is

Turn FSM into a blackbox, much like PSM is

- Similar in spirit to PSM blackbox treatment in
  commit df9cdb1321ada8e3b120771f91a2eefab4ac2ad5, except that
  technically fsm guts are still wide-open in fsm.h due to cpio
  "needing" them (yuck).
- Allows getting rid of dumb a**-backwards things like rpmfiFSM()
  which is just not needed, fsm is a relatively short-lived entity
  inside psm and build, nobody else needs to bother with it except
  for the returned results.
- Figure out the cpio map flags in fsmSetup() where it logically belongs,
  we have all the necessary info available there.
- Get rid of newFSM() and freeFSM(), we can just as well place the
  fsm on stack, merge the necessary cleanup bits from freeFSM()
  into fsmTeardown()
- Supposedly no functional changes, knock wood.