[PATCH] Makeconfig: Use $(error ...) to output error message

[Florian Weimer]

* Maciej W. Rozycki:

> Hi Simon,
>
>> Thanks, could you please push it for me?  I don't have write access to the
>> glibc repo (and don't plan to make enough contributions to justify it).
>
>  FTR I don't think you need any additional credentials to push to any of 
> the repos hosted at sourceware as long as you have an account there, and 
> obviously you do.

You need to be added to the project-specific POSIX group, though.