Fix some compilation warnings

src/collapsestateproxymodel.cpp

@@ -8,6 +8,7 @@
 
 bool CollapseStateProxyModel::filterAcceptsRow(int source_row, const QModelIndex &source_parent) const
 {
+    Q_UNUSED(source_parent);
     return sourceModel()->data(sourceModel()->index(source_row, 0), MessageEventModel::EventTypeRole)
         != QLatin1String("state") // If this is not a state, show it
         || sourceModel()->data(sourceModel()->index(source_row + 1, 0), MessageEventModel::EventTypeRole)

src/controller.cpp

@@ -574,7 +574,7 @@ void Controller::setActiveConnection(Connection *connection)
     m_connection = connection;
     if (connection != nullptr) {
         NeoChatConfig::self()->setActiveConnection(connection->userId());
-        connect(connection, &Connection::networkError, this, [this](QString message, QString details, int retriesTaken, int nextRetryInMilliseconds) {
+        connect(connection, &Connection::networkError, this, [this]() {
             if (!m_isOnline) {
                 return;
             }

src/devicesmodel.cpp

@@ -11,7 +11,7 @@
 DevicesModel::DevicesModel(QObject *parent)
     : QAbstractListModel(parent)
 {
-    connect(&Controller::instance(), &Controller::activeConnectionChanged, this, [=]() {
+    connect(&Controller::instance(), &Controller::activeConnectionChanged, this, [this]() {
         DevicesModel::fetchDevices();
         Q_EMIT connectionChanged();
     });