atapi_request_sense() is now the only left user of ata_sg_init_one().
Convert it to use sg interface.
Signed-off-by: NTejun Heo <htejun@gmail.com>
Cc: Rusty Russel <rusty@rustcorp.com.au>
Signed-off-by: NJeff Garzik <jeff@garzik.org>