re: port-sparc64/56829: miniroot.fs no longer boots

[matthew green <mrg%eterna.com.au@localhost>]

this appears to be a bad call to "map", in both ofwboot and the
kernel itself.  Harold tested a change i suggested in ofwboot
where the OF_map_phys() code was changed to not have any returns
(the 1275 docs don't list any), and it works in qemu.

for ofwboot, OF_map_phys() needs the "status" and "retaddr"
members removed from the "args", and the "if (args.status)"
code removed, and the success return value switched to 0,
not args.retaddr.

for the kernel, similar for prom_map_phys() is probably needed.


.mrg.