iio: imu: adis16400: fix memory leak

In adis_update_scan_mode_burst, if adis->buffer allocation fails release
the adis->xfer.

Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
Reviewed-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/imu/adis_buffer.c

@@ -35,8 +35,11 @@ static int adis_update_scan_mode_burst(struct iio_dev *indio_dev,
 		return -ENOMEM;
 
 	adis->buffer = kzalloc(burst_length + sizeof(u16), GFP_KERNEL);
-	if (!adis->buffer)
+	if (!adis->buffer) {
+		kfree(adis->xfer);
+		adis->xfer = NULL;
 		return -ENOMEM;
+	}
 
 	tx = adis->buffer + burst_length;
 	tx[0] = ADIS_READ_REG(adis->burst->reg_cmd);