[Patch] Increase buffer size due to warning from ToT GCC

[Joseph Myers]

On Fri, 15 Dec 2017, Steve Ellcey wrote:

> Here is a patch to fix it, OK to checkin?

OK.  (I doubt there would actually be truncation here, but it's 
locale-dependent, so making this buffer large enough to ensure that only 
the previous format operations can result in truncation, and this one 
can't, seems reasonable.)

-- 
Joseph S. Myers
joseph@codesourcery.com