can: grcan: fix spelling mistake "buss" -> "bus"

There is a spelling mistake in a netdev_err error message. Fix it.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20200806105616.46790-1-colin.king@canonical.com


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