To benefit from special filters for single SFF or single EFF CAN identifier
subscriptions the CAN_EFF_FLAG bit and the CAN_RTR_FLAG bit has to be set
together with the CAN_(SFF|EFF)_MASK in can_filter.mask.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>