The new setup.c


The role of setup.c, now, is just calling them, in order

 for (f = __initcall_begin; f < __initcall_end; f++) {
         errors += (*f)();


And, obviously, we panic if any fails

As a side effect, we alway link in usleep and its init code
Panic calls usleep

How could we solve the problem?
If the target CPU is very small, we want to avoid panic()
... while keeping the same code structure overall