ide: use try_to_identify() in ide_driveid_update()

* Pass pointer to buffer for IDENTIFY data to do_identify()
  and try_to_identify().

* Un-static try_to_identify() and use it in ide_driveid_update().

* Rename try_to_identify() to ide_dev_read_id().

There should be no functional changes caused by this patch.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>