VIO devices were being looked up by their index in the machine
description node block, but this often varies over time as devices are
added and removed. Instead, store the ID and look up using the type,
config handle and ID.
Signed-off-by: NJames Clarke <jrtc27@jrtc27.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=112541Signed-off-by: NDavid S. Miller <davem@davemloft.net>