video: use gpio_request_one

Using gpio_request_one can make the code simpler because it can
set the direction and initial value in one shot.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Michael Hennerich <michael.hennerich@analog.com>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>