docs-rst: add package adjustbox

We need adjustbox to allow adjusting the size of tables that
are bigger than the line width. There are quite a few of them
at the media books.

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
1 file changed