iio: light: as73211: Ensure buffer holes are zeroed

Given that the buffer is copied to a kfifo that ultimately user space
can read, ensure we zero it.

Fixes: 403e558 ("iio: light: as73211: New driver")
Reviewed-by: Matti Vaittinen <mazziesaccount@gmail.com>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Link: https://patch.msgid.link/20250802164436.515988-2-jic23@kernel.org
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

Author: jic23

drivers/iio/light/as73211.c

@@ -639,7 +639,7 @@ static irqreturn_t as73211_trigger_handler(int irq __always_unused, void *p)
 	struct {
 		__le16 chan[4];
 		aligned_s64 ts;
-	} scan;
+	} scan = { };
 	int data_result, ret;
 
 	mutex_lock(&data->mutex);