Nice-to-have fix for autogen.sh

[Pete Batard]

On 2012.02.01 17:39, Segher Boessenkool wrote:
>> Except for the fact that configure is really slow, I'd agree with you.
>
> It doesn't take more than ten seconds on a really slow machine though,
> so it is almost bearable...

Actually, I'm well placed to know that configure is an order of 
magnitude slower (I'm not kidding) if you're using MinGW or cygwin on 
Windows. I could actually provide timings of the exact same machine 
(dual core, 4 GB RAM) running the same libusb configure if you want to 
see for yourselves.

So I will agree with Vitali that configure can be and is really slow on 
some platforms.

Regards,

/Pete