drm/nouveau/iccsense: convert to linked list

v2: add list_del calls

Signed-off-by: Karol Herbst <nouveau@karolherbst.de>
Reviewed-by: Martin Peres <martin.peres@free.fr>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/nouveau_hwmon.c

@@ -689,7 +689,7 @@ nouveau_hwmon_init(struct drm_device *dev)
 			goto error;
 	}
 
-	if (iccsense && iccsense->data_valid && iccsense->rail_count) {
+	if (iccsense && iccsense->data_valid && !list_empty(&iccsense->rails)) {
 		ret = sysfs_create_group(&hwmon_dev->kobj,
 					 &hwmon_power_attrgroup);
 		if (ret)