Qt6 migration fixes: RTI DDS alias targets, ErrorMessage namespace, DDS header include path

qt6-after/qt6-migrated-legatus/Lts/Tools/QLedLine/qledline.cpp

@@ -11,7 +11,7 @@
 #include <QtCore/QString>
 #include <QLayout>
 #include <QtCore/QTimer>
-#include <QImage>
+#include <QtGui/QImage>
 
 #include "qledchar.h"
 
@@ -29,7 +29,7 @@ QLedLine::QLedLine(QWidget *parent)
 {
   m_layout->setSpacing(0);
   m_layout->setContentsMargins(0,0,0,0);
-  m_layout->setMargin(0);
+  m_layout->setContentsMargins(0, 0, 0, 0);
 
   QSpacerItem *sp1 = new QSpacerItem(0,0, QSizePolicy::Expanding, QSizePolicy::Expanding);
   QSpacerItem *sp2 = new QSpacerItem(0,0, QSizePolicy::Expanding, QSizePolicy::Expanding);