Fix over-4GiB seek on sparc64.
* include/grub/ieee1275/ieee1275.h (grub_ieee1275_seek):
Replace pos_i and pos_lo with pos. All users updated.
* include/grub/powerpc/ieee1275/ieee1275.h (GRUB_IEEE1275_CELL_SIZEOF):
New constant.
* include/grub/sparc64/ieee1275/ieee1275.h (GRUB_IEEE1275_CELL_SIZEOF):
Likewise.
* kern/ieee1275/ieee1275.c (grub_ieee1275_seek): Split pos into pos_hi
and pos_lo.
ca62070b69