staging:iio:buffer.h update struct buffer docs.

These docs have lagged recent developments.

Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/staging/iio/buffer.h b/drivers/staging/iio/buffer.h
index 9b1a4f1..c697099 100644
--- a/drivers/staging/iio/buffer.h
+++ b/drivers/staging/iio/buffer.h
@@ -70,9 +70,15 @@
  * @scan_el_attrs:	[DRIVER] control of scan elements if that scan mode
  *			control method is used
  * @scan_mask:		[INTERN] bitmask used in masking scan mode elements
+ * @scan_index_timestamp:[INTERN] cache of the index to the timestamp
  * @scan_timestamp:	[INTERN] does the scan mode include a timestamp
  * @access:		[DRIVER] buffer access functions associated with the
  *			implementation.
+ * @scan_el_dev_attr_list:[INTERN] list of scan element related attributes.
+ * @scan_el_group:	[DRIVER] attribute group for those attributes not
+ *			created from the iio_chan_info array.
+ * @pollq:		[INTERN] wait queue to allow for polling on the buffer.
+ * @stufftoread:	[INTERN] flag to indicate new data.
  * @flags:		[INTERN] file ops related flags including busy flag.
  * @demux_list:		[INTERN] list of operations required to demux the scan.
  * @demux_bounce:	[INTERN] buffer for doing gather from incoming scan.