macio: move ESCC device within the macio device

macio: move ESCC device within the macio device

Now that the ESCC device is instantiated directly via qdev, move it to within
the macio device and wire up the IRQs and memory regions using the sysbus API.

This enables to remove the now-obsolete escc_mem parameter to the macio_init()
function.

(Note this patch also contains small touch-ups to the formatting in
macio_escc_legacy_setup() and ppc_heathrow_init() in order to keep checkpatch
happy)

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>