McuSupport: Automatic memory management for mcu sdk

Fix crash while automatically restoring kits during startup.
Change packages container to set to avoid duplicates.
Use RAII for McuSdkRepository.

Change-Id: I4b3f4156f0bc770c8a5ea8a171b1f22f6ffb8f96
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>
Reviewed-by: Alessandro Portale <alessandro.portale@qt.io>

src/plugins/mcusupport/mcupackage.h

@@ -64,6 +64,8 @@ public:
                const bool addToPath = false,
                const Utils::FilePath &relativePathModifier = Utils::FilePath());
 
+    ~McuPackage() override = default;
+
     QString label() const override;
     const QString &cmakeVariableName() const override;
     const QString &environmentVariableName() const override;
@@ -89,7 +91,6 @@ private:
     void updatePath();
     void updateStatusUi();
 
-    QWidget *m_widget = nullptr;
     Utils::PathChooser *m_fileChooser = nullptr;
     Utils::InfoLabel *m_infoLabel = nullptr;
 
@@ -113,6 +114,7 @@ private:
 
 class McuToolChainPackage : public McuPackage
 {
+    Q_OBJECT
 public:
     enum class ToolChainType { IAR, KEIL, MSVC, GCC, ArmGcc, GHS, GHSArm, Unsupported };