Nice-to-have fix for autogen.sh

[Segher Boessenkool]

>>> Sorry.  I think there should be a second auto-gen that's for  
>>> people who check out from the repository but want to build a  
>>> release build.
>>
>> They can run configure by hand, after running autogen.sh, whether
>> autogen.sh already runs configure or not; any run of configure
>> completely overrides anything a previous run did.

> Except for the fact that configure is really slow, I'd agree with you.

Yeah, there is that.  But running autogen.sh is a lot slower than just
configure already :-(

It doesn't take more than ten seconds on a really slow machine though,
so it is almost bearable...


Segher