Sigh… I guess we’re doing this!

The term cpu-hotplug in the arm world almost never means hot-adding a new package/die to the platform, we usually mean taking CPUs online/offline for power management. e.g. cpuhp_offline_cpu_device()

https://www.spinics.net/lists/arm-kernel/msg739722.html

That's marketing overloading a term, not technology.