can: tcan4x5x: remove unused struct tcan4x5x_priv::tcan4x5x_lock

The mutex struct tcan4x5x_priv::tcan4x5x_lock is unused in the driver,
so this patch removes the variable from the driver.

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