media: tc358743: validate lane count

The TC358743 does not support more than 4 data lanes. Check that the
lane count is valid.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>