Small patch to enable build of gdb-7.6 for GNU/Hurd

[Svante Signell]

On Fri, 2013-05-24 at 09:53 +0100, Pedro Alves wrote:
> On 05/24/2013 05:27 AM, Joel Brobecker wrote:
> > On Thu, May 23, 2013 at 11:59:46PM -0300, Sergio Durigan Junior wrote:
> >> Thanks for your patch, Svante.
> >>
> >> On Thursday, May 23 2013, Svante Signell wrote:
> >>
...
> > And quite honestly, I find this use of a macro in the middle of
> > a function quite ugly and unnecessary, no matter what was done
> > before.  My preference mirrors Tom's suggestion, but failing that,
> > I'd rather FMT be a const char * or a const char [].
> 
> Agreed.
> 
> const char fmt[] = "..." is better than 'const char *', as the
> latter gives you an unnecessary extra pointer.
> 
> Make that 'static const char fmt[] = "...";' even.
> 
> But really alloca for potentially large/unbounded buffers is evil.
> xstrprintf plus a cleanup would definitely be my preference.

I will change to use xstrprintf instead. Updated patch with ChangeLog
entry will follow shortly. Is it OK to modify also the other (preceding)
function in the same way (for consistency)?