regulator: fix kernel-doc warning in consumer.h

From: Randy Dunlap <[email protected]>

Fix kernel-doc warning about internal/private data by marking it as "private:" so that kernel-doc will ignore it.

Warning(include/linux/regulator/consumer.h:128): No description found for parameter 'ret'

---
 include/linux/regulator/consumer.h |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -123,7 +123,7 @@ struct regulator_bulk_data {
 	const char *supply;
 	struct regulator *consumer;
 
-	/* Internal use */
+	/* private: Internal use */
 	int ret;
 };