mlxsw: spectrum_router: Pass non-register proto enum to __mlxsw_sp_router_set_abort_trap()

Don't pass RALXX register enum and rather pass enum mlxsw_sp_l3proto
to __mlxsw_sp_router_set_abort_trap(). This is in preparation to fib
entry pack implementation by XMDR register.

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