[v3] Remove uses of <cstddef> as an implementation detail

[Johannes Singler]

Paolo Carlini wrote:
> It is of course Ok, at least for now.
> 
> Could be the reason of a weird issue reported by Johannes Singler
> which didn't make any sense to me (I don't have any machine running
> those glibcs), sorry about that.

Well, YaST says that glibc 2.9-2.12.1 (all automatic updates installed)
is installed on my machines, and they do show these problems.  glibc 2.9
was released on Nov 13, 2008, but the bug was fixed only on Dec 29,
2008.  So there might also be affected systems running glibc 2.9, and I
really wonder why it worked on any openSuse 11.1.

<http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44417>

Johannes