[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/libsas/sas_port.c b/drivers/scsi/libsas/sas_port.c
index 1398b71..d3c5297 100644
--- a/drivers/scsi/libsas/sas_port.c
+++ b/drivers/scsi/libsas/sas_port.c
@@ -69,7 +69,7 @@
 			continue;
 		}
 
-		if (dev->dev_type == EDGE_DEV || dev->dev_type == FANOUT_DEV) {
+		if (dev->dev_type == SAS_EDGE_EXPANDER_DEVICE || dev->dev_type == SAS_FANOUT_EXPANDER_DEVICE) {
 			dev->ex_dev.ex_change_count = -1;
 			for (i = 0; i < dev->ex_dev.num_phys; i++) {
 				struct ex_phy *phy = &dev->ex_dev.ex_phy[i];