platform/x86: int3472: Add board data for Dell 7212

The Dell 7212 Rugged Extreme Tablet pairs an OV5670 sensor with the
Intel IPU3 ISP. The sensor is powered by a TPS68470 PMIC, and so we
need some board data to describe how to configure the GPIOs and
regulators to run the sensor.

Signed-off-by: Daniel Scally <dan.scally@ideasonboard.com>
Acked-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>