npu2: Reset NVLinks on hot reset
npu2: Reset NVLinks on hot reset

This effectively fences GPU RAM on GPU reset so the host system
does not have to crash every time we stop a KVM guest with a GPU
passed through.

Suggested-by: Balbir Singh <ac7b77b73f9d2cc0faddd296218dde0558e170e3@gmail.com>
Signed-off-by: Alexey Kardashevskiy <ac1fc56530d7d037e1ea666f130daca22d72f964@ozlabs.ru>
Acked-by: Balbir Singh <ac7b77b73f9d2cc0faddd296218dde0558e170e3@gmail.com>
Signed-off-by: Stewart Smith <ec31ab75ddf977353c8f660f92ea8b23f64aef25@linux.ibm.com>

open-power/skiboot,qemu/skiboot,shenki/skiboot,open-power/skiboot,qemu/skiboot,legoater/skiboot,stewart-ibm/skiboot,qemu/skiboot,shenki/skiboot,legoater/skiboot,legoater/skiboot,qemu/skiboot,legoater/skiboot,stewart-ibm/skiboot,open-power/skiboot,shenki/skiboot,shenki/skiboot,open-power/skiboot,stewart-ibm/skiboot,legoater/skiboot,open-power/skiboot,qemu/skiboot,shenki/skiboot