drm: bridge: it66121: Extend match support for OF tables

The driver has OF match table, still it uses ID lookup table for
retrieving match data. Currently the driver is working on the
assumption that a I2C device registered via OF will always match a
legacy I2C device ID. The correct approach is to have an OF device ID
table using of_device_match_data() if the devices are registered via OF.

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Robert Foss <rfoss@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230818191817.340360-2-biju.das.jz@bp.renesas.com