Bump cppcheck to v2.11

This fixes the following errors:-

sesman/tools/authtest.c:64:14: error: syntax error [syntaxError]
    g_printf("xrdp auth module tester v" PACKAGE_VERSION "\n");
             ^
sesman/tools/sesrun.c:165:14: error: syntax error [syntaxError]
    g_printf("xrdp session starter v" PACKAGE_VERSION "\n");
             ^
vrplayer/decoder.h:35:12: error: There is an unknown macro here somewhere. Configuration is required. If slots is a macro then please configure it. [unknownMacro]
    public slots:
           ^
vrplayer/playaudio.h:45:12: error: There is an unknown macro here somewhere. Configuration is required. If slots is a macro then please configure it. [unknownMacro]
    public slots:
           ^
vrplayer/dlgabout.h:22:13: error: There is an unknown macro here somewhere. Configuration is required. If slots is a macro then please configure it. [unknownMacro]
    private slots:
            ^
vrplayer/playvideo.h:49:12: error: There is an unknown macro here somewhere. Configuration is required. If slots is a macro then please configure it. [unknownMacro]
    public slots:
           ^
Additionally, cppcheck now makes use of all available CPUs

vrplayer/decoder.h

@@ -32,7 +32,7 @@ class Decoder : public QObject
 
     signals:
 
-    public slots:
+    public slots: // cppcheck-suppress unknownMacro
         void onGeometryChanged(QRect *geometry);
 };
 

vrplayer/dlgabout.h

@@ -19,7 +19,7 @@ class DlgAbout : public QDialog
     private:
         Ui::DlgAbout *ui;
 
-    private slots:
+    private slots: // cppcheck-suppress unknownMacro
         void onOk();
 };
 

vrplayer/playaudio.h

@@ -42,7 +42,7 @@ class PlayAudio : public QObject
 
         void setVcrOp(int op);
 
-    public slots:
+    public slots: // cppcheck-suppress unknownMacro
         void play();
 
     private:

vrplayer/playvideo.h

@@ -46,7 +46,7 @@ class PlayVideo : public QObject
         //void setVcrOp(int op);
         //void onMediaRestarted();
 
-    public slots:
+    public slots: // cppcheck-suppress unknownMacro
         void play();
 
         //signals: