Increase width of padded output in stdio-common/tst-put-error

[Siddhesh Poyarekar]

> I thought the point of the padded test was to verify the path for errors 
> propagating through _IO_padn - which requires the error to occur while the 
> padding itself is being passed to _IO_sputn (that is, for the padding to 
> fill the buffer itself) rather than when anything after the padding causes 
> a flush.
> 

The bug wasn't limited to libio, i.e. it wasn't just _IO_padn or
_IO_sputn; even the *printf functions were not really set up to
receive the error.  The common aspect I saw between the two tests in
tst-put-error is that they're verifying that *printf correctly fails
if it cannot flush its buffer.


Siddhesh