mlxsw: spectrum_router: Pass virtual router parameters directly instead of pointer

mlxsw_sp_adj_index_mass_update_vr() only needs the virtual router's
identifier and protocol, so pass them directly. In a subsequent patch
the caller will not have access to the pointer.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>