[SCSI] libsas: convert ha->state to flags

In preparation for adding new states (SAS_HA_DRAINING, SAS_HA_FROZEN),
convert ha->state into a set of flags.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
diff --git a/drivers/scsi/libsas/sas_internal.h b/drivers/scsi/libsas/sas_internal.h
index 7fe4ede..1fd84b3 100644
--- a/drivers/scsi/libsas/sas_internal.h
+++ b/drivers/scsi/libsas/sas_internal.h
@@ -100,7 +100,7 @@
 		unsigned long flags;
 
 		spin_lock_irqsave(&sas_ha->state_lock, flags);
-		if (sas_ha->state != SAS_HA_UNREGISTERED)
+		if (test_bit(SAS_HA_REGISTERED, &sas_ha->state))
 			scsi_queue_work(sas_ha->core.shost, work);
 		spin_unlock_irqrestore(&sas_ha->state_lock, flags);
 	}