libata: fix kernel-doc warnings

Fix libata kernel-doc warnings:

Warning(linux-next-20090120//drivers/ata/libata-core.c:4720): Excess function parameter 'dev' description in 'ata_qc_new'
Warning(linux-next-20090120//drivers/ata/libata-scsi.c:428): No description found for parameter 'ap'
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

drivers/ata/libata-core.c

@@ -4709,8 +4709,7 @@ void swap_buf_le16(u16 *buf, unsigned int buf_words)
 
 /**
  *	ata_qc_new - Request an available ATA command, for queueing
- *	@ap: Port associated with device @dev
- *	@dev: Device from whom we request an available command structure
+ *	@ap: target port
  *
  *	LOCKING:
  *	None.

drivers/ata/libata-scsi.c

@@ -415,6 +415,7 @@ int ata_std_bios_param(struct scsi_device *sdev, struct block_device *bdev,
 
 /**
  *	ata_get_identity - Handler for HDIO_GET_IDENTITY ioctl
+ *	@ap: target port
  *	@sdev: SCSI device to get identify data for
  *	@arg: User buffer area for identify data
  *