RDMA/rxe: Remove useless rxe_init_device_param assignments

IB devices are allocated with kzalloc and don't need explicit zero
assignments for their parameters. It can be removed safely.

Link: https://lore.kernel.org/r/20191020055724.7410-1-leon@kernel.org


Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>