mlxsw: spectrum_router: Allow programming link-local host routes

Cited commit added the ability to program link-local prefix routes to
the ASIC so that relevant packets are routed and trapped correctly.

However, host routes were not included in the change and thus not
programmed to the ASIC. This can result in packets being trapped via an
external route trap instead of a local route trap as in IPv4.

Fix this by programming all the link-local routes to the ASIC.

Fixes: 10d3757f ("mlxsw: spectrum_router: Allow programming link-local prefix routes")
Reported-by: Alex Veber <alexve@mellanox.com>
Tested-by: Alex Veber <alexve@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>