Sensorhub  is MCU dedicated to collect data and manage several sensors.
Sensorhub is a spi device which provides a layer for IIO devices. It provides
some data parsing and common mechanism for sensorhub sensors.

Adds common sensorhub library for sensorhub driver and iio drivers
which uses sensorhub MCU to communicate with sensors.
Signed-off-by: NKarol Wrona <k.wrona@samsung.com>
Acked-by: NKyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>