RDMA/rxe: Fix wrong port_cap_flags

The port->attr.port_cap_flags should be set to enum
ib_port_capability_mask_bits in ib_mad.h, not
RDMA_CORE_CAP_PROT_ROCE_UDP_ENCAP.

Fixes: 8700e3e7 ("Soft RoCE driver")
Link: https://lore.kernel.org/r/20210831083223.65797-1-weijunji@bytedance.com


Signed-off-by: Junji Wei <weijunji@bytedance.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>