Codechange: use NetworkAddress instead of two host/port variables where possible

This also means we no longer need last_host/last_port, but can
just use a single last_joined setting.

src/network/core/address.cpp

@@ -101,8 +101,8 @@ void NetworkAddress::GetAddressAsString(char *buffer, const char *last, bool wit
  */
 std::string NetworkAddress::GetAddressAsString(bool with_family)
 {
-	/* 6 = for the : and 5 for the decimal port number */
-	char buf[NETWORK_HOSTNAME_LENGTH + 6 + 7];
+	/* 7 extra are for with_family, which adds " (IPvX)". */
+	char buf[NETWORK_HOSTNAME_PORT_LENGTH + 7];
 	this->GetAddressAsString(buf, lastof(buf), with_family);
 	return buf;
 }