IB/mthca: NULL arg to pci_dev_put is OK

The pci_dev_put() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/hw/mthca/mthca_reset.c

@@ -279,8 +279,7 @@ int mthca_reset(struct mthca_dev *mdev)
 	}
 
 out:
-	if (bridge)
-		pci_dev_put(bridge);
+	pci_dev_put(bridge);
 	kfree(bridge_header);
 	kfree(hca_header);