A VSX-PCT patch for glibc

[H.J. Lu]

> > BTW, there are bugs in VSX-PCT also :-).
> 
> I would have bet on this.  When I ran the PCTS I stopped counting at
> about 50 bugs in the testsuite.
> 

BTW, VSX-PCT checks if stdin/stdout/stderr are defined as macros.
Is that required by ANSI C? I thought external variables were ok.
Could someone please verify it?

Thanks.

H.J.