iio: imu: inv_mpu6050: add WoM (Wake-on-Motion) sensor

WoM is a threshold test on accel value comparing actual sample with
previous one. It maps best to roc rising event.

Add support of a new WOM sensor and functions for handling the associated
roc_rising event. The event value is in SI units. Ensure WOM is stopped and
restarted at suspend-resume, handle usage with buffer data ready interrupt,
and handle change in sampling rate impacting already set roc value.

Signed-off-by: Jean-Baptiste Maneyrol <jean-baptiste.maneyrol@tdk.com>
Link: https://lore.kernel.org/r/20240311160557.437337-2-inv.git-commit@tdk.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>