MEDIUM: init: remove the loop over processes during init

MEDIUM: init: remove the loop over processes during init

There was a loop iterating over all nbproc values during init that
couldn't be immediately removed because the loop's index was used
to distinguish a child from a parent. That's now fixed by replacing
the iterator with an in_parent flag. All bindings that were checking
(1UL << proc) or cpu_map.proc[proc] were adjusted to always use zero
for proc.