nvidia does not create nor install those packages. The package is created by rpmfusion to support the nvidia drivers.
I beleve that the nvidia-power package provides the following and without those services sleeping or suspending would not work properly. I think it also only works for certain GPUs so may not be useful in all cases.
# rpm -qal xorg-x11-drv-nvidia-power
/usr/bin/nvidia-powerd
/usr/bin/nvidia-sleep.sh
/usr/lib/modprobe.d/nvidia-power-management.conf
/usr/lib/systemd/system-preset/70-nvidia.preset
/usr/lib/systemd/system-sleep/nvidia
/usr/lib/systemd/system/nvidia-hibernate.service
/usr/lib/systemd/system/nvidia-powerd.service
/usr/lib/systemd/system/nvidia-resume.service
/usr/lib/systemd/system/nvidia-suspend.service
/usr/share/dbus-1/system.d/nvidia-dbus.conf