Remove at:urban maxspeed, partial revert of 2bbb347f57 (#6450)

profiles/car.lua

@@ -268,7 +268,6 @@ function setup()
 
     -- List only exceptions
     maxspeed_table = {
-      ["at:urban"] = 40,
       ["at:rural"] = 100,
       ["at:trunk"] = 100,
       ["be:motorway"] = 120,

taginfo.json

@@ -146,7 +146,6 @@
         {"key": "maxspeed", "value": "rural"},
         {"key": "maxspeed", "value": "trunk"},
         {"key": "maxspeed", "value": "motorway"},
-        {"key": "maxspeed", "value": "AT:urban"},
         {"key": "maxspeed", "value": "AT:rural"},
         {"key": "maxspeed", "value": "AT:trunk"},
         {"key": "maxspeed", "value": "BE:motorway"},