can: isotp: remove ISO 15675-2 specification version where possible

can: isotp: remove ISO 15675-2 specification version where possible

With the new ISO 15765-2:2024 release the former documentation and comments
have to be reworked. This patch removes the ISO specification version/date
where possible.

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Acked-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Acked-by: Francesco Valla <valla.francesco@gmail.com>
Link: https://lore.kernel.org/all/20240420194746.4885-1-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>