staging: iio: timestamp_en naming typo fix.

Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/iio/ring_generic.h

@@ -276,7 +276,7 @@ ssize_t iio_scan_el_ts_show(struct device *dev, struct device_attribute *attr,
  **/
 #define IIO_SCAN_EL_TIMESTAMP(number)				\
 	struct iio_scan_el iio_scan_el_timestamp = {		\
-		.dev_attr = __ATTR(_timestamp_en,		\
+		.dev_attr = __ATTR(timestamp_en,		\
 				   S_IRUGO | S_IWUSR,		\
 				   iio_scan_el_ts_show,		\
 				   iio_scan_el_ts_store),	\