ata: pata_sil680: Add some missing function parameter docs

Fixes the following W=1 kernel build warning(s):

 drivers/ata/pata_sil680.c:68: warning: Function parameter or member 'adev' not described in 'sil680_seldev'
 drivers/ata/pata_sil680.c:254: warning: Function parameter or member 'try_mmio' not described in 'sil680_init_chip'

Cc: Jens Axboe <axboe@kernel.dk>
Cc: Andre Hedrick <andre@linux-ide.org>
Cc: Red Hat <alan@redhat.com>
Cc: linux-ide@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20210318085150.3131936-3-lee.jones@linaro.orgSigned-off-by: Jens Axboe <axboe@kernel.dk>

drivers/ata/pata_sil680.c

@@ -57,6 +57,7 @@ static unsigned long sil680_selreg(struct ata_port *ap, int r)
 /**
  *	sil680_seldev		-	return register base
  *	@ap: ATA interface
+ *	@adev: ATA device
  *	@r: config offset
  *
  *	Turn a config register offset into the right address in PCI space
@@ -244,6 +245,7 @@ static struct ata_port_operations sil680_port_ops = {
 /**
  *	sil680_init_chip		-	chip setup
  *	@pdev: PCI device
+ *	@try_mmio: Indicates to caller whether MMIO should be attempted
  *
  *	Perform all the chip setup which must be done both when the device
  *	is powered up on boot and when we resume in case we resumed from RAM.