Replacing unowned city roads does not change speed limit

[ceeac]

Steps to reproduce:

• Have a city with unowned city roads (i.e. not owned by any player, including the public service)
• In-game, replace some of these roads by a road with higher speed limit (e.g. 50km/h -> 130 km/h)
• Notice that while the graphics of the road change, the speed limit does not

This does not happen if the existing road is owned by the public player.

[prissi]

Oh, it did, but a max in that function left it at their max speed and vice versa (because max instead min). Please check r11914, I hope I fixed it.