regulator: Mark attributes table for virtual regulator static

It's not exported.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
diff --git a/drivers/regulator/virtual.c b/drivers/regulator/virtual.c
index 45ebbc2..3d08348 100644
--- a/drivers/regulator/virtual.c
+++ b/drivers/regulator/virtual.c
@@ -260,7 +260,7 @@
 static DEVICE_ATTR(max_microamps, 0666, show_max_uA, set_max_uA);
 static DEVICE_ATTR(mode, 0666, show_mode, set_mode);
 
-struct device_attribute *attributes[] = {
+static struct device_attribute *attributes[] = {
 	&dev_attr_min_microvolts,
 	&dev_attr_max_microvolts,
 	&dev_attr_min_microamps,