This patch changes all the iterator code to use a prefix ++ instead
of postfix since it is more efficient (no need for a temporary). It
is likely that the compiler could optimize this away, but lets make
it efficient from the start.
It is possible for defparams to not find their target the first time
around, because the elaboration of the target scope is not yet done.
So retry the defparams once for each scope by putting it on a work
item in the elaborator_work_items list.