media: vivid: Add metadata capture support

This patch adds meatadata capture support in vivid driver.
Adds new files for metadata capture.
Adds vivid controls to generate PTS and SCR for metadata stream.
also fixes v4l2-compliance issues seen on metadata device.

Signed-off-by: Vandana BN <bnvandana@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>