IB/isert: set rdma cm afonly flag

This will allow both IPv4 and IPv6 sockets to bind a single port at the
same time. Same behaviour is implemented in NVMe/RDMA target.

Link: https://lore.kernel.org/r/20210524085225.29064-1-mgurtovoy@nvidia.com


Reviewed-by: Alaa Hleihel <alaa@nvidia.com>
Reviewed-by: Israel Rukshin <israelr@nvidia.com>
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>