[SCSI] sas: unify the pointlessly separated enums sas_dev_type and sas_device_type

These enums have been separate since the dawn of SAS, mainly because the
latter is a procotol only enum and the former includes additional state
for libsas.  The dichotomy causes endless confusion about which one you
should use where and leads to pointless warnings like this:

drivers/scsi/mvsas/mv_sas.c: In function 'mvs_update_phyinfo':
drivers/scsi/mvsas/mv_sas.c:1162:34: warning: comparison between 'enum sas_device_type' and 'enum sas_dev_type' [-Wenum-compare]

Fix by eliminating one of them.  The one kept is effectively the sas.h
one, but call it sas_device_type and make sure the enums are all
properly namespaced with the SAS_ prefix.

Signed-off-by: James Bottomley <JBottomley@Parallels.com>
diff --git a/drivers/scsi/isci/request.c b/drivers/scsi/isci/request.c
index 9594ab6..e3e3bcb 100644
--- a/drivers/scsi/isci/request.c
+++ b/drivers/scsi/isci/request.c
@@ -2978,7 +2978,7 @@
 	/* all unaccelerated request types (non ssp or ncq) handled with
 	 * substates
 	 */
-	if (!task && dev->dev_type == SAS_END_DEV) {
+	if (!task && dev->dev_type == SAS_END_DEVICE) {
 		state = SCI_REQ_TASK_WAIT_TC_COMP;
 	} else if (task && task->task_proto == SAS_PROTOCOL_SMP) {
 		state = SCI_REQ_SMP_WAIT_RESP;
@@ -3101,7 +3101,7 @@
 	if (idev->rnc.remote_node_index == SCIC_SDS_REMOTE_NODE_CONTEXT_INVALID_INDEX)
 		return SCI_FAILURE_INVALID_REMOTE_DEVICE;
 
-	if (dev->dev_type == SAS_END_DEV)
+	if (dev->dev_type == SAS_END_DEVICE)
 		/* pass */;
 	else if (dev_is_sata(dev))
 		memset(&ireq->stp.cmd, 0, sizeof(ireq->stp.cmd));
@@ -3125,7 +3125,7 @@
 	/* Build the common part of the request */
 	sci_general_request_construct(ihost, idev, ireq);
 
-	if (dev->dev_type == SAS_END_DEV || dev_is_sata(dev)) {
+	if (dev->dev_type == SAS_END_DEVICE || dev_is_sata(dev)) {
 		set_bit(IREQ_TMF, &ireq->flags);
 		memset(ireq->tc, 0, sizeof(struct scu_task_context));