can: mcan: m_can_class_unregister(): fix order of unregistration calls

If a driver is removed, the driver framework invokes the driver's
remove callback. A CAN driver's remove function calls
unregister_candev(), which calls net_device_ops::ndo_stop further down
in the call stack for interfaces which are in the "up" state.

The removal of the module causes a warning, as can_rx_offload_del()
deletes the NAPI, while it is still active, because the interface is
still up.

To fix the warning, first unregister the network interface, which
calls net_device_ops::ndo_stop, which disables the NAPI, and then call
can_rx_offload_del().

Fixes: 1be37d3 ("can: m_can: fix periph RX path: use rx-offload to ensure skbs are sent from softirq context")
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20250502-can-rx-offload-del-v1-3-59a9b131589d@pengutronix.de
Reviewed-by: Markus Schneider-Pargmann <msp@baylibre.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

Author: marckleinebudde

drivers/net/can/m_can/m_can.c

@@ -2463,9 +2463,9 @@ EXPORT_SYMBOL_GPL(m_can_class_register);
 
 void m_can_class_unregister(struct m_can_classdev *cdev)
 {
+	unregister_candev(cdev->net);
 	if (cdev->is_peripheral)
 		can_rx_offload_del(&cdev->offload);
-	unregister_candev(cdev->net);
 }
 EXPORT_SYMBOL_GPL(m_can_class_unregister);