iio: dummy: Switch to iio_push_to_buffers_with_ts() and provide size of storage

Provide the storage size so that the helper can sanity check that it
is large enough for the configured channels.

Reviewed-by: Nuno Sá <[e-mail]>
Reviewed-by: David Lechner <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Jonathan Cameron <[e-mail]>

drivers/iio/dummy/iio_simple_dummy_buffer.c

···
 	iio_for_each_active_channel(indio_dev, j)
 		scan->data[i++] = fakedata[j];
 
-	iio_push_to_buffers_with_timestamp(indio_dev, scan,
-					   iio_get_time_ns(indio_dev));
+	iio_push_to_buffers_with_ts(indio_dev, scan, sizeof(*scan),
+				    iio_get_time_ns(indio_dev));
 
 	kfree(scan);
 done: