The radiusclient-ng project is dead for quite many years, and has been replaced by the freeradius-client project which provides a compatible library. Please, consider switching your project to the new library.
Note that, the libraries are API-compatible. Most probably you'll only need to change the include file to <freeradius-client.h> and link against -lfreeradius-client.
This bug appears to have been reported against 'rawhide' during the Fedora 23 development cycle. Changing version to '23'. (As we did not run this process for some time, it could affect also pre-Fedora 23 development cycle bugs. We are very sorry. It will help us with cleanup during Fedora 23 End Of Life. Thank you.) More information and reason for this action is here: https://fedoraproject.org/wiki/BugZappers/HouseKeeping/Fedora23
Please note that this is now critical as radiusclient-ng will be dropped in F24. If you need this functionality either depend on freeradius-client-devel or radcli (the radcli-compat-devel is API compatible with radiusclient-ng).
opensips-1.10.5-9.fc24 fails to build in F24 because radiusclient-ng was removed for F24.
*** Bug 1307833 has been marked as a duplicate of this bug. ***