Also switch macio_newworld_realize() over to use it rather than using the pic_mem
memory region directly.
Now that both Old World and New World macio devices no longer make use of the
pic_mem memory region directly, we can remove it.
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>