Fix clang-tidy wanings a and a missng initalization

src/control/controlcompressingproxy.cpp

@@ -4,7 +4,7 @@
 
 namespace {
 constexpr int kMaxNumOfRecursions = 128;
-}
+} // namespace
 
 // Event queue compressing proxy
 CompressingProxy::CompressingProxy(const ConfigKey& key,

src/control/controlindicator.cpp

@@ -6,7 +6,7 @@
 
 namespace {
 const QString kAppGroup = QStringLiteral("[App]");
-}
+} // namespace
 
 ControlIndicator::ControlIndicator(const ConfigKey& key)
         : ControlObject(key, false),

src/controllers/controlpickermenu.cpp

@@ -13,7 +13,7 @@
 
 namespace {
 const QString kAppGroup = QStringLiteral("[App]");
-}
+} // namespace
 
 ControlPickerMenu::ControlPickerMenu(QWidget* pParent)
         : QMenu(pParent) {

src/controllers/delegates/midioptionsdelegate.cpp

@@ -28,7 +28,7 @@ const QList<MidiOption> kMidiOptions = {
         MidiOption::FourteenBitLSB,
 };
 
-}
+} // namespace
 
 MidiOptionsDelegate::MidiOptionsDelegate(QObject* pParent)
         : QStyledItemDelegate(pParent) {

src/controllers/midi/portmidicontroller.cpp

@@ -5,7 +5,7 @@
 
 namespace {
 const QString kUnknownControllerName = QStringLiteral("Unknown PortMidiController");
-}
+} // namespace
 
 PortMidiController::PortMidiController(const PmDeviceInfo* inputDeviceInfo,
         const PmDeviceInfo* outputDeviceInfo,

src/effects/backends/lv2/lv2effectprocessor.cpp

@@ -5,6 +5,7 @@
 
 LV2EffectProcessor::LV2EffectProcessor(LV2EffectManifestPointer pManifest)
         : m_pManifest(pManifest),
+          m_LV2parameters(nullptr),
           m_pPlugin(pManifest->getPlugin()),
           m_audioPortIndices(pManifest->getAudioPortIndices()),
           m_controlPortIndices(pManifest->getControlPortIndices()) {

src/effects/presets/effectpresetmanager.cpp

@@ -8,7 +8,7 @@
 
 namespace {
 const QString kEffectDefaultsDirectory = "/effects/defaults";
-}
+} // namespace
 
 EffectPresetManager::EffectPresetManager(UserSettingsPointer pConfig,
         EffectsBackendManagerPointer pBackendManager)

src/engine/controls/loopingcontrol.cpp

@@ -21,7 +21,7 @@ constexpr mixxx::audio::FrameDiff_t kMinimumAudibleLoopSizeFrames = 150;
 bool positionNear(mixxx::audio::FramePos a, mixxx::audio::FramePos target) {
     return a.isValid() && a > target - 1 && a < target + 1;
 }
-}
+} // namespace
 
 double LoopingControl::s_dBeatSizes[] = { 0.03125, 0.0625, 0.125, 0.25, 0.5,
                                           1, 2, 4, 8, 16, 32, 64, 128, 256, 512 };

src/engine/enginemixer.cpp

@@ -30,7 +30,7 @@
 
 namespace {
 const QString kAppGroup = QStringLiteral("[App]");
-}
+} // namespace
 
 EngineMixer::EngineMixer(
         UserSettingsPointer pConfig,

src/library/library.cpp

@@ -50,7 +50,7 @@ namespace {
 
 const mixxx::Logger kLogger("Library");
 
-} // anonymous namespace
+} // namespace
 
 using namespace mixxx::library::prefs;
 

src/library/trackset/setlogfeature.cpp

@@ -22,7 +22,7 @@
 
 namespace {
 constexpr int kNumToplevelHistoryEntries = 5;
-}
+} // namespace
 
 using namespace mixxx::library::prefs;