V4L/DVB (5730): Remove unused V4L2_CAP_VIDEO_OUTPUT_POS

V4L2_CAP_VIDEO_OUTPUT_POS was initially introduced for 2.6.22 but never
actually used: remove it before the final 2.6.22 is made.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>