Fix compatibility with C++17.

Signed-off-by: Slávek Banko <slavek.banko@axis.cz>

lanbrowsing/lisa/netmanager.h

@@ -77,7 +77,7 @@ class NetManager:public NetScanner
       int m_increasedRefreshTime;
       int m_broadcastAddress;
       std::list<Client> clients;
-      struct client_is_done : std::unary_function<Client, bool>
+      struct client_is_done : std::function<bool(Client)>
       {
          bool operator() (Client& c)
          {

lanbrowsing/lisa/netscanner.h

@@ -88,7 +88,7 @@ class NetScanner
       int hostAlreadyInList(int ip, std::list<Node>* nodes);
       void removeUnnamedHosts(std::list<Node>* nodes);
 
-      struct is_unnamed_node : std::unary_function<Node&, bool>
+      struct is_unnamed_node : std::function<bool(Node&)>
       {
          bool operator() (Node& n)
          {