video: mb862xx: Remove redundant dev_set_drvdata

Driver core sets driver data to NULL upon failure or remove.

Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Acked-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>