authserver round robin and multiple NAS-IP-Address avpairs

[Alan DeKok]

Stefan Karss wrote:
> when configuring round-robin authservers in sendserver.c function
> "rc_send_server" the NAS-IP-Address gets added for each fail-overed
> server resulting in the NAS-IP-Address avpair being sent multiple times.
> I fixed it by checking for presence of NAS-IP-Address avpair (see patch).

  Looks good, thanks.

  Alan DeKok.