This fixes regression introduced in 5a0c810462 with which all requests
for link properties ended up with EINVAL as we kept hitting
the signature_is_single() assert in sd_bus_get_property().
This fixes regression introduced in 5a0c810462 with which all requests
for link properties ended up with EINVAL as we kept hitting
the signature_is_single() assert in sd_bus_get_property().