For reduce "if" condition, easy to read/understand the code,
optimize "if" condition in rx/tx processing.
Signed-off-by: NTomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Acked-by: NMarc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>