iio:imu:adis16480: fix buffering for devices with no burst mode

iio:imu:adis16480: fix buffering for devices with no burst mode

The trigger handler defined in the driver assumes that burst mode is
being used. Hence, for devices that do not support it, we have to use
the adis library default trigger implementation.

Tested-by: Julia Pineda <julia.pineda@analog.com>
Fixes: 941f130881fa9 ("iio: adis16480: support burst read function")
Signed-off-by: Nuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20220114132608.241-1-nuno.sa@analog.com
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>