[PATCH] resolv: Remove support for RES_USE_INET6 and the inet6 option

[Florian Weimer]

* Florian Weimer:

> * Florian Weimer:
>
>> This functionality was deprecated in glibc 2.25.
>
> Do you think we can remove the functionality, or should we wait some
> more time?

I'm going to commit this to master soon.  I asked on dns-operations, and
no one wants to keep this interface:

<https://lists.dns-oarc.net/pipermail/dns-operations/2019-February/018384.html>

Thanks,
Florian