intent in cfg_layout_initialize

[DJ Delorie]

In cfg_layout_initialize, there's a call to cleanup_cfg:

  cleanup_cfg (CLEANUP_CFGLAYOUT);

There's no comment here as to the intent.  Is it expected to do lots
of (or any) optimizations?  Some are disabled in cfgcleanup.c when
this flag is set, but not all.  Specifically, on an internal port I'm
working on, enough optimization happens to invalidate the live
registers list, and I get the ubiquitous "verify_local_live_at_start"
error.

Should we (or could we) be passing CLEANUP_UPDATE_LIFE here?  Or
should I dig into cfgcleanup.c and disable more optimizations?  Or is
something else happening?