RZ/G2L has separate channel specific IRQs for transmit and error
interrupts. But the IRQ handler processes both channels, even if there
no interrupt occurred on one of the channels.

This patch fixes the issue by passing a channel specific context
parameter instead of global one for the IRQ register and the IRQ
handler, it just handles the channel which is triggered the interrupt.

Fixes: 76e9353a ("can: rcar_canfd: Add support for RZ/G2L family")
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Link: https://lore.kernel.org/all/20221025155657.1426948-3-biju.das.jz@bp.renesas.com
Cc: stable@vger.kernel.org
[mkl: adjust commit message]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>