Add __wur for GNU strerror_r()

[Roland McGrath]

That seems like a sensible change to me.  It needs a proper ChangeLog
entry.  As it's a feature change rather than a bug fix per se, it will
wait until after the 2.16 freeze unless Carlos deems otherwise.

It's probably wise to file it in bugzilla so we don't lose track of it.


Thanks,
Roland