can: make function can_get_bittiming static

The function can_get_bittiming is not used anywhere else, so it should be
static.
Signed-off-by: NThadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/can/dev.c

@@ -208,7 +208,7 @@ static int can_fixup_bittiming(struct net_device *dev, struct can_bittiming *bt)
 	return 0;
 }
 
-int can_get_bittiming(struct net_device *dev, struct can_bittiming *bt)
+static int can_get_bittiming(struct net_device *dev, struct can_bittiming *bt)
 {
 	struct can_priv *priv = netdev_priv(dev);
 	int err;