Codechange: [Network] split CloseSocket and CloseConnection more clearly (#9261)

* Codechange: [Network] split CloseSocket and CloseConnection more clearly

- CloseSocket now closes the actual OS socket.
- CloseConnection frees up the resources to just before CloseSocket.
- dtors call CloseSocket / CloseConnection where needed.

src/network/core/udp.cpp

@@ -44,7 +44,7 @@ NetworkUDPSocketHandler::NetworkUDPSocketHandler(NetworkAddressList *bind)
 bool NetworkUDPSocketHandler::Listen()
 {
 	/* Make sure socket is closed */
-	this->Close();
+	this->CloseSocket();
 
 	for (NetworkAddress &addr : this->bind) {
 		addr.Listen(SOCK_DGRAM, &this->sockets);
@@ -54,9 +54,9 @@ bool NetworkUDPSocketHandler::Listen()
 }
 
 /**
- * Close the given UDP socket
+ * Close the actual UDP socket.
  */
-void NetworkUDPSocketHandler::Close()
+void NetworkUDPSocketHandler::CloseSocket()
 {
 	for (auto &s : this->sockets) {
 		closesocket(s.second);
@@ -64,12 +64,6 @@ void NetworkUDPSocketHandler::Close()
 	this->sockets.clear();
 }
 
-NetworkRecvStatus NetworkUDPSocketHandler::CloseConnection(bool error)
-{
-	NetworkSocketHandler::CloseConnection(error);
-	return NETWORK_RECV_STATUS_OKAY;
-}
-
 /**
  * Send a packet over UDP
  * @param p    the packet to send