media: i2c: imx214: Check number of lanes from device tree

The imx214 camera is capable of either two-lane or four-lane operation.

Currently only the four-lane mode is supported, as proper pixel rates
and link frequences for the two-lane mode are unknown.

Acked-by: Ricardo Ribalda <ribalda@chromium.org>
Signed-off-by: André Apitzsch <git@apitzsch.eu>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>