[SCSI] libsas: fixup target_port_protocols for expanders that don't report sata

If discovery returns 0 for target_port_protocols but shows an attached
sata device, just report SAS_PROTOCOL_SATA in the identify data so
userspace can reliably search for sata devices in the domain.

Signed-off-by: Dan Williams <[e-mail]>
Signed-off-by: James Bottomley <[e-mail]>

drivers/scsi/libsas/sas_expander.c

···
 	phy->phy->identify.device_type = dr->attached_dev_type;
 	phy->phy->identify.initiator_port_protocols = phy->attached_iproto;
 	phy->phy->identify.target_port_protocols = phy->attached_tproto;
+	if (!phy->attached_tproto && dr->attached_sata_dev)
+		phy->phy->identify.target_port_protocols = SAS_PROTOCOL_SATA;
 	phy->phy->identify.phy_identifier = phy_id;
 	phy->phy->minimum_linkrate_hw = dr->hmin_linkrate;
 	phy->phy->maximum_linkrate_hw = dr->hmax_linkrate;