[media] V4L2: platform: rcar_jpu: remove redundant code

Remove redundant code. Following code line do what we want.

[mchehab@osg.samsung.com: fix conflict with VB2 split patches that renamed some structs]
Signed-off-by: Mikhail Ulyanov <mikhail.ulyanov@cogentembedded.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>