RDMA/ocrdma: Remove unsupported modify_port callback

There is no need to return always zero for function which is not
supported.

Fixes: fe2caefc ("RDMA/ocrdma: Add driver for Emulex OneConnect IBoE RDMA adapter")
Link: https://lore.kernel.org/r/20191028155931.1114-4-kamalheib1@gmail.com


Signed-off-by: Kamal Heib <kamalheib1@gmail.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>