[media] v4l: exynos4-is: Drop unneeded check when setting up fimc-lite links

The driver verifies that the type of the remote entity matches its
expectations when setting up fimc-lite links and returns an error if it
doesn't. Those checks can never fail as the links are created by the
driver in a way that always match its expectations (the SINK and
SOURCE_ISP pads are connected to subdevs only and the SOURCE_DMA pad is
connected to a video node only). Remove them.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>