Move the remaining comment into macio.c for reference, then remove the
macio_init() function and instantiate the macio devices for both Old World
and New World machines via qdev_init_nofail() directly.
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>