RDMA/cma: add missed unregister_pernet_subsys in init failure

The driver forgets to call unregister_pernet_subsys() in the error path
of cma_init().
Add the missed call to fix it.

Fixes: 4be74b4 ("IB/cma: Separate port allocation to network namespaces")
Signed-off-by: Chuhong Yuan <[email protected]>
Reviewed-by: Parav Pandit <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Doug Ledford <[email protected]>

Author: WillLester

drivers/infiniband/core/cma.c

@@ -4763,6 +4763,7 @@ static int __init cma_init(void)
 err:
 	unregister_netdevice_notifier(&cma_nb);
 	ib_sa_unregister_client(&sa_client);
+	unregister_pernet_subsys(&cma_pernet_operations);
 err_wq:
 	destroy_workqueue(cma_wq);
 	return ret;