Documentation: process: Arbitrarily bump kernel major version number

Documentation: process: Arbitrarily bump kernel major version number

The big picture section of 2.Process.rst currently hardcodes major
version number to 5 since fb0e0ffe7fc8e0 ("Documentation: bring process
docs up to date"). As it can get outdated when it is actually
incremented (the recent is 6 and will be 7 in the near future),
arbitrarily bump it to 9, giving a headroom for a decade.

Note that the version number examples are kept to illustrate the
numbering scheme.

Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
[jc: tweaked the initial 9.x mention slightly]
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20250922074219.26241-1-bagasdotme@gmail.com>