RDMA/cma: Skip device which doesn't support CM

RDMA/cma: Skip device which doesn't support CM

A switchdev RDMA device do not support IB CM. When such device is added to
the RDMA CM's device list, when application invokes rdma_listen(), cma
attempts to listen to such device, however it has IB CM attribute
disabled.

Due to this, rdma_listen() call fails to listen for other non switchdev
devices as well.

A below error message can be seen.

infiniband mlx5_0: RDMA CMA: cma_listen_on_dev, error -38

A failing call flow is below.

  cma_listen_on_all()
    cma_listen_on_dev()
      _cma_attach_to_dev()
        rdma_listen() <- fails on a specific switchdev device

This is because rdma_listen() is hardwired to only work with iwarp or IB
CM compatible devices.

Hence, when a IB device doesn't support IB CM or IW CM, avoid adding such
device to the cma list so rdma_listen() can't even be called.

Link: https://lore.kernel.org/r/f9cac00d52864ea7c61295e43fb64cf4db4fdae6.1618753862.git.leonro@nvidia.com
Signed-off-by: Parav Pandit <parav@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>