The removal of mlx5 flow steering logic, left the kernel without any RDMA
drivers that implements flow action callbacks supplied by RDMA/core. Any
user access to them caused to EOPNOTSUPP error, which can be achieved by
simply removing ioctl implementation.

Link: https://lore.kernel.org/r/a638e376314a2eb1c66f597c0bbeeab2e5de7faf.1649232994.git.leonro@nvidia.comReviewed-by: Raed Salem <raeds@nvidia.com>
Acked-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>