pci bus rescan from userland

[Yuri Pankov]

Hi,

Trying to enable the HDMI/DP sound output on NVIDIA Quadro M2200, I have 
found the following workaround on NVIDIA Linux forums 
(https://devtalk.nvidia.com/default/topic/1024022/linux/gtx-1060-no-audio-over-hdmi-only-hda-intel-detected-azalia/post/5211273/#5211273):

setpci -s 01:00.0 0x488.l=0x2000000:0x2000000
rmmod nvidia-drm nvidia-modeset nvidia
echo 1 > /sys/bus/pci/devices/0000:01:00.0/remove
echo 1 > /sys/bus/pci/devices/0000:00:01.0/rescan
modprobe nvidia-drm

So far rmmod and modprobe steps are obvious, setpci works as well (I 
guess I could use pciconf? doesn't really matter).  Is there a FreeBSD 
equivalent of doing the remove/rescan steps from userland?