ATA: remove excess kernel-doc notation

Remove excess kernel-doc function parameter notation from drivers/ata/:

Warning(drivers/ata/libata-core.c:1622): Excess function parameter or struct member 'fn' description in 'ata_pio_queue_task'
Warning(drivers/ata/libata-core.c:4655): Excess function parameter or struct member 'err_mask' description in 'ata_qc_complete'
Warning(drivers/ata/ata_piix.c:751): Excess function parameter or struct member 'udma' description in 'do_pata_set_dmamode'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>