iio: Pass scan mask as unsigned long

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c
index 58180ec..2361fbc 100644
--- a/drivers/iio/industrialio-buffer.c
+++ b/drivers/iio/industrialio-buffer.c
@@ -429,8 +429,8 @@
 	return NULL;
 }
 
-static int iio_compute_scan_bytes(struct iio_dev *indio_dev, const long *mask,
-				  bool timestamp)
+static int iio_compute_scan_bytes(struct iio_dev *indio_dev,
+				const unsigned long *mask, bool timestamp)
 {
 	const struct iio_chan_spec *ch;
 	unsigned bytes = 0;