[media] media: soc_camera: rcar_vin: Fix wait_for_completion

When stopping abnormally, a driver can't return from wait_for_completion.
This patch resolved this problem by changing wait_for_completion_timeout
from wait_for_completion.

Signed-off-by: Koji Matsuoka <koji.matsuoka.xm@renesas.com>
Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>