Fix warning in optimize build.
Fix typo.
ia32: allow any entity size in MemPerm lowering

The new spillslot coalescing sometimes produces 2byte memperms which the
old code couldn't handle.
disable reload folding for x87 nodes for now

We have a bad situation here as at the time of reload folding we can't
predict yet whether the spillslot coalescer must enlarge the spillslot
to 80bit precision.
For now I fix it by not folding reloads into x87 nodes. The better
alternative which I didn't do yet are:
- Move the spillslot coalescing to an earlier place before reload
  folding. This is somewhat tricky as the reload folding is implemented
  in generic code, while coalescing is backend specific.
- Revert folded AM when the spillslot is widened.
ia32: do not force 32/64 stackends if not necessary

This should fix 400.perlbench which was using a 16bit stackent here.