slw: Enable stop states on P9P
slw: Enable stop states on P9P

Enable stop states on P9P for the Swift platform.

Signed-off-by: Ryan Grimm <b82eecdfce19ef6c0125840b498d3afc6226dd31@linux.ibm.com>
[oliver: fixed patch title]
Signed-off-by: Oliver O'Halloran <3dfaff8fa6ae977f042064a112a6aac576279b9b@gmail.com>

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