birdc 2.0.0 crashes

[Clemens Schrimpe]

> Could you try to build bird/birdc (without any patches i sent before) using:
> 
>  make CLIENT_LIBS="-lreadline -ltinfo"
> 
> ?

And indeed, this fixes it and persistent history still works! 

\o/

	Clemens

PS: for your records (again) - this machine run Ubuntu 16.04.3 LTS in a (mostly) vanilla fashion. I just installed libreadline6-dbg to help with this case. So the same problem/solution *should* apply on other machines as well!?