add "unknown" as possible value for access fields

dist/translations/ar.json

@@ -4949,8 +4949,8 @@
                     "terms": "كاميرا مراقبة السرعة"
                 },
                 "highway/steps": {
-                    "name": "درج",
-                    "terms": "درج"
+                    "name": "درج/سلم",
+                    "terms": "درج,سلم"
                 },
                 "highway/steps/conveying": {
                     "name": "سلم كهربائي",

dist/translations/en.json

@@ -64,6 +64,7 @@
                         "permissive": "Permissive",
                         "customers": "Customers Only",
                         "permit": "By Permit Only",
+                        "unknown": "Unknown",
                         "no": "None"
                     }
                 },
@@ -109,6 +110,10 @@
                         "permit": {
                             "title": "Permit",
                             "description": "Access allowed only with a valid permit or license"
+                        },
+                        "unknown": {
+                            "title": "Unknown",
+                            "description": "Access conditions are unknown or unclear"
                         }
                     }
                 },
@@ -6370,6 +6375,10 @@
                     "name": "Point",
                     "terms": "node,other,vertex,vertices"
                 },
+                "police/checkpoint": {
+                    "name": "Police Checkpoint",
+                    "terms": "checkpoint,patrol,roadblock,spot check,stop"
+                },
                 "polling_station": {
                     "name": "Temporary Polling Place",
                     "terms": "ballot box,ballot drop,democracy,elections,polling place,vote,voting booth,voting machine"