net-snmp checks for libelf in its configure script and links to it. The apparent reason for this is that it wants to to use libelf to poke around in /dev/kmem on some non-Linux systems.
Release -6 of the RPM has a patch from Florian that says it prevents the build from trying to use -lelf (it replaces it with -llelf, which I guess is supposed to make -lelf not found during configure). However, during the build, it still links with -lelf in the last step, which will fail if libelf-devel is not installed (see bug 76086). I think either 76086 needs to be implemented (so libelf-devel is properly required during build), or this one should be implemented (so libelf is truly not needed).
Fixed in net-snmp-5.0.6-9 rawhide build.