mapport: rename 'use_pcp' to 'enable'

There is only a single protocol now, caller should just be concerned about whether to enable port mapping or not.

src/interfaces/node.h

@@ -121,7 +121,7 @@ public:
     virtual void resetSettings() = 0;
 
     //! Map port.
-    virtual void mapPort(bool use_pcp) = 0;
+    virtual void mapPort(bool enable) = 0;
 
     //! Get proxy.
     virtual bool getProxy(Network net, Proxy& proxy_info) = 0;

src/mapport.cpp

@@ -166,9 +166,9 @@ static void MapPortProtoSetEnabled(bool enabled)
     g_mapport_enabled = enabled;
 }
 
-void StartMapPort(bool use_pcp)
+void StartMapPort(bool enable)
 {
-    MapPortProtoSetEnabled(use_pcp);
+    MapPortProtoSetEnabled(enable);
     DispatchMapPort();
 }
 

src/mapport.h

@@ -7,7 +7,7 @@
 
 static constexpr bool DEFAULT_NATPMP = false;
 
-void StartMapPort(bool use_pcp);
+void StartMapPort(bool enable);
 void InterruptMapPort();
 void StopMapPort();
 

src/node/interfaces.cpp

@@ -187,7 +187,7 @@ public:
         });
         args().WriteSettingsFile();
     }
-    void mapPort(bool use_pcp) override { StartMapPort(use_pcp); }
+    void mapPort(bool enable) override { StartMapPort(enable); }
     bool getProxy(Network net, Proxy& proxy_info) override { return GetProxy(net, proxy_info); }
     size_t getNodeCount(ConnectionDirection flags) override
     {