dt-bindings: iio: imu: add icm42688 inside inv_icm42600

Add bindings for ICM-42688-P chip.

Signed-off-by: Jean-Baptiste Maneyrol <jean-baptiste.maneyrol@tdk.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20240408090720.847107-2-inv.git-commit@tdk.com


Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>