can: Proper ctrlmode handling for CAN devices

This patch adds error checking of ctrlmode values for CAN devices. As
an example all availabe bits are implemented in the mcp251x driver.

Signed-off-by: Christian Pellegrin <chripell@fsfe.org>
Acked-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/can/ti_hecc.c b/drivers/net/can/ti_hecc.c
index 7d370e3..8332e24 100644
--- a/drivers/net/can/ti_hecc.c
+++ b/drivers/net/can/ti_hecc.c
@@ -909,6 +909,7 @@
 	priv->can.bittiming_const = &ti_hecc_bittiming_const;
 	priv->can.do_set_mode = ti_hecc_do_set_mode;
 	priv->can.do_get_state = ti_hecc_get_state;
+	priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES;
 
 	ndev->irq = irq->start;
 	ndev->flags |= IFF_ECHO;