[slurm-users] Development RPMs for cgroups v2

I am building a version of Slurm on RHEL 9.4 When I run an rpmbuild, he slurm rpm does not contain /usr/lib64/slurm/cgroup_v2.so

I have tried to look in the build logs. I suspect I am lacking some development RPMs - but which ones?

All hints gratefully received John H