dts: add support for p9 cores
dts: add support for p9 cores

P9 cores have two DTS (the location unit is unknown to me for the
moment) which have the same encoding than on the P8.

Signed-off-by: Cédric Le Goater <2d8cace2254d4e43578d21933db015d84bcc468a@kaod.org>
Signed-off-by: Stewart Smith <ec31ab75ddf977353c8f660f92ea8b23f64aef25@linux.vnet.ibm.com>

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