dt-bindings: media: et8ek8: Deprecate clock-frequency property

dt-bindings: media: et8ek8: Deprecate clock-frequency property

Usage of the clock-frequency property for camera sensors is discouraged
in favour of using assigned-clock-rates (and assigned-clock-parents
where needed). Drop the property, and update the example accordingly.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Mehdi Djait <mehdi.djait@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>