[PATCH] linux: Simplify get_nprocs

[Florian Weimer]

* Adhemerval Zanella:

> Although currently we already call get_nprocs on some internal usages
> (malloc for instance) and I haven't see any regression with my change.
> Do we really need to add an explicit test for it?

Yes, we want to know if such large systems arrive.  Think of it as a
reminder for something that might happen twenty years from now.

Thanks,
Florian