QmlDesigner: Fix crash

Check for existing device.

Task-number: QDS-10137
Change-Id: I00065b63f09fb5691c52acaefd75fee0c4315d75
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>
Reviewed-by: Qt CI Patch Build Bot <ci_patchbuild_bot@qt.io>

src/plugins/qmldesigner/components/toolbar/toolbarbackend.cpp

@@ -27,6 +27,7 @@
 #include <projectexplorer/projectmanager.h>
 #include <projectexplorer/target.h>
 
+#include <projectexplorer/devicesupport/idevice.h>
 #include <qmlprojectmanager/qmlproject.h>
 #include <qtsupport/qtkitinformation.h>
 
@@ -621,7 +622,10 @@ QStringList ToolBarBackend::kits() const
 {
     auto kits = Utils::filtered(ProjectExplorer::KitManager::kits(), [](ProjectExplorer::Kit *kit) {
         const auto qtVersion = QtSupport::QtKitAspect::qtVersion(kit);
+        const auto dev = ProjectExplorer::DeviceKitAspect::device(kit);
+
         return kit->isValid() && !kit->isReplacementKit() && qtVersion && qtVersion->isValid()
+               && dev
             /*&& kit->isAutoDetected() */;
     });