pch_can: fix module reload issue with MSI

Currently, in case reload pch_can,
pch_can not to be able to catch interrupt.

The cause is bus-master is not set in pch_can.
Thus, add enabling bus-master processing.

Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/can/pch_can.c b/drivers/net/can/pch_can.c
index 342d514..7d8bc12 100644
--- a/drivers/net/can/pch_can.c
+++ b/drivers/net/can/pch_can.c
@@ -1238,6 +1238,7 @@
 		priv->use_msi = 0;
 	} else {
 		netdev_err(ndev, "PCH CAN opened with MSI\n");
+		pci_set_master(pdev);
 		priv->use_msi = 1;
 	}