ata: pata_parport-bpck6: remove useless defines

Almost all the ATAPI_ defines are unused. Remove them and use
ATA_REG_DATA instead of ATAPI_DATA.

Signed-off-by: Ondrej Zary <linux@zary.sk>
Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>