can: m_can: Always acknowledge all interrupts

The code already exits the function on !ir before this condition. No
need to check again if anything is set as IR_ALL_INT is 0xffffffff.

Signed-off-by: Markus Schneider-Pargmann <msp@baylibre.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Link: https://lore.kernel.org/all/20230315110546.2518305-3-msp@baylibre.com


Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>