Move code inside exit1() to better spots.

Move code inside exit1() to better spots.

- PS_PROFIL bit is moved into the process cleanup block where it belongs
- The proc read-only limit cache cleanup is moved up right after clearing
  p->p_fd cache. lim_free() can potentially sleep and so needs to be
  above the line where p_stat is set to SDEAD.

With and OK jca@