can: rcar_canfd: Add {nom,data}_bittiming variables to struct rcar_canfd_hw_info

can: rcar_canfd: Add {nom,data}_bittiming variables to struct rcar_canfd_hw_info

Both R-Car Gen4 and R-Car Gen3 have different bit timing parameters
Add {nom,data}_bittiming variables to struct rcar_canfd_hw_info to
handle this difference.

Since the mask used in the macros are max value - 1, replace that
as well.

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://patch.msgid.link/20250417054320.14100-13-biju.das.jz@bp.renesas.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>