media: v4l: Fix missing tabular column hint for Y14P format

The original patch added two columns in the flat-table of Luma-Only
Image Formats, without updating hints to latex: above it.  This results
in wrong column count in the output of Sphinx's latex builder.

Fix it.

Reported-by: Akira Yokosawa <akiyks@gmail.com>
Closes: https://lore.kernel.org/linux-media/bdbc27ba-5098-49fb-aabf-753c81361cc7@gmail.com/


Fixes: adb1d465 ("media: v4l: Add V4L2-PIX-FMT-Y14P format")
Cc: stable@vger.kernel.org # for v6.10
Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@yoseli.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>