[media] s5p-mfc: Fix setting controls

Fixed s_ctrl function when setting the following controls:
- V4L2_CID_MPEG_VIDEO_DECODER_MPEG4_DEBLOCK_FILTER
- V4L2_CID_MPEG_MFC51_VIDEO_DECODER_H264_DISPLAY_DELAY

Signed-off-by: Kamil Debski <k.debski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>