[media] saa7164: fix querycap warning

Fix the VIDIOC_QUERYCAP warning due to the missing device_caps. Don't fill
in the version field, the V4L2 core will do that for you.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Cc: <stable@vger.kernel.org>      # for v3.19 and up
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>