RDMA/cma: Set default GID type as RoCE when resolving RoCE route

As the function name suggests cma_resolve_iboe_route() resolves RoCE
route. However, its default GID type is IB_GID_TYPE_IB and not
IB_GID_TYPE_ROCE, even though both are mapped to the same enum value.
Change default GID type to IB_GID_TYPE_ROCE.

cma_iboe_set_mgid() is updated to reflect the RoCEv2 GID check.

Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Reviewed-by: Noa Osherovich <noaos@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>