Documentation: process: replace outdated LTS table w/ link

The existing table was a bit outdated.

3.16 was EOL in 2020.
4.4 was EOL in 2022.

5.10 is new in 2020.
5.15 is new in 2021.

We'll see if 6.1 becomes LTS in 2022.

Rather than keep this table updated, it does duplicate information from
multiple kernel.org pages. Make one less duplication site that needs to
be updated and simply refer to the kernel.org page on releases.

Suggested-by: Tyler Hicks <code@tyhicks.com>
Suggested-by: Bagas Sanjaya <bagasdotme@gmail.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/stable/20221014171040.849726-1-ndesaulniers%40google.com


Reviewed-by: Tyler Hicks (Microsoft) <code@tyhicks.com>
Link: https://lore.kernel.org/r/20221014171040.849726-1-ndesaulniers@google.com


Signed-off-by: Jonathan Corbet <corbet@lwn.net>