[media] v4l: mt9v032: Remove unneeded header

The of_gpio.h header isn't needed, don't include it.

Reported-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>