[SCSI] pm80xx: Phy settings support for motherboard controller.

Phy profile implementation to support phy settings feature
for motherboard controllers.

[jejb: checkpatch fixes]
Signed-off-by:  <Anandkumar.Santhanam@pmcs.com>
Reviewed-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>