In /drivers/block/ata_piix.h, ata_id_has_lba48(), ata_id_has_lba(),
ata_id_has_dma(), ata_id_u32(), ata_id_u64() are all defined in
include/libata.h which is included in ata.h which is included by all files
which include ata_piix.h (only ata_piix.c) so these definitions are
supurflous to (and conlict with) this in libata.h. Interestingly, my
compiler complains about ata_id_u64 already being defined, but not
ata_id_u32
ata_dump_id() is defined in include/libata.h and should not be static
(maybe should even use ata_dump_id() in libata.c