ata: libata: Add ata_port_classify() helper

Add an ata_port_classify() helper to print out the results from
the device classification and remove the debugging statements
from ata_dev_classify().

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>