hw/p8-i2c: Move port init into a separate function
hw/p8-i2c: Move port init into a separate function

Move it out in preparation for adding the ability to add new ports on
the fly.

Signed-off-by: Oliver O'Halloran <3dfaff8fa6ae977f042064a112a6aac576279b9b@gmail.com>
Signed-off-by: Vasant Hegde <a6d753843573f7bfed5075c1e875b0be8007a0ab@linux.vnet.ibm.com>

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