iio: Drop timestamp parameter from buffer store_to callback

Drop timestamp parameter from buffer store_to callback and subsequently from
iio_push_to_buffer. The timestamp parameter is unused and it seems likely that
it will stay unused in the future, so it should be safe to remove it.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
diff --git a/drivers/iio/light/hid-sensor-als.c b/drivers/iio/light/hid-sensor-als.c
index b3c8e91..96e3691 100644
--- a/drivers/iio/light/hid-sensor-als.c
+++ b/drivers/iio/light/hid-sensor-als.c
@@ -177,7 +177,6 @@
 static void hid_sensor_push_data(struct iio_dev *indio_dev, u8 *data, int len)
 {
 	struct iio_buffer *buffer = indio_dev->buffer;
-	s64 timestamp = iio_get_time_ns();
 	int datum_sz;
 
 	dev_dbg(&indio_dev->dev, "hid_sensor_push_data\n");
@@ -191,7 +190,7 @@
 				datum_sz);
 		return;
 	}
-	iio_push_to_buffer(buffer, (u8 *)data, timestamp);
+	iio_push_to_buffer(buffer, (u8 *)data);
 }
 
 /* Callback handler to send event after all samples are received and captured */