[media] videodev2.h: fix copy-and-paste error in V4L2_MAP_XFER_FUNC_DEFAULT

The colorspace argument was compared against a V4L2_XFER_FUNC define instead
of against a V4L2_COLORSPACE define, returning the wrong answer.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>