[PATCH][v2] Clean pthread types namespace for all archs.

[Joseph Myers]

The general structure of this patch seems right to me, though since the 
justification of the patch is as part of the C11 threads implementation, 
the detailed review may make most sense when you have a full patch series 
implementing C11 threads ready to submit.  (Until then, it still makes 
sense to post successive patches for comments as you complete them, and to 
maintain a git branch somewhere with the current patch series, rebased as 
needed.  But it's less clear if the individual patches should go into 
master until more of the patch series is ready.)

-- 
Joseph S. Myers
joseph@codesourcery.com