[master] radmin build error with no USE_READLINE (radmin_main_config)

[Alan DeKok]

> On Aug 24, 2018, at 5:14 AM, Chaigneau, Nicolas <nicolas.chaigneau at capgemini.com> wrote:
> The following is defined within a "#ifdef USE_READLINE" (src/bin/radmin.c)
> ...
> 
> I moved "radmin_main_config" out of the ifdef so it would build.

  I've pushed a fix, thanks.

  Alan DeKok.