Do not allow the second instance of Partition Manager

BUG: 365882

CMakeLists.txt

@@ -51,6 +51,7 @@ find_package(KF5 5.23 REQUIRED
   ConfigWidgets
   CoreAddons
   Crash
+  DBusAddons
   DocTools
   I18n
   IconThemes

src/CMakeLists.txt

@@ -44,6 +44,7 @@ target_link_libraries(partitionmanager ${BLKID_LIBRARIES}
 	KF5::ConfigWidgets
 	KF5::CoreAddons
 	KF5::Crash
+	KF5::DBusAddons
 	KF5::I18n
 	KF5::IconThemes
 	KF5::JobWidgets

src/main.cpp

@@ -28,6 +28,7 @@
 
 #include <KAboutData>
 #include <KCrash>
+#include <KDBusService>
 #include <Kdelibs4ConfigMigrator>
 #include <KMessageBox>
 #include <KLocalizedString>
@@ -85,6 +86,8 @@ int Q_DECL_IMPORT main(int argc, char* argv[])
     if (!loadBackend())
         return 0;
 
+    KDBusService service(KDBusService::Unique);
+
     MainWindow* mainWindow = new MainWindow();
     mainWindow->show();