iio: imu: adis16480: use state lock for filter freq set

It's the only operation that does 2 operations (a read & a write), so the
unlocked functions can be used under a single state lock.

Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
1 file changed