Fix some clazy warning

Modules/base/info_wayland.cpp

@@ -72,7 +72,7 @@ void WaylandModule::init()
             queue->setup(m_connection);
             registry->setEventQueue(queue);
             connect(registry, &Registry::interfaceAnnounced, this,
-                [this, interfacesItem] (QByteArray interface, quint32 name, quint32 version) {
+                [this, interfacesItem] (const QByteArray &interface, quint32 name, quint32 version) {
                     Q_UNUSED(name)
                     new QTreeWidgetItem(interfacesItem, QStringList() << interface << QString::number(version));
                 }

Modules/base/os_base.h

@@ -218,7 +218,6 @@ static bool GetInfo_XServer_Generic(QTreeWidget *lBox) {
 	Display *dpy;
 	XPixmapFormatValues *pmf;
 
-	QString str, txt;
 	QTreeWidgetItem *last, *item, *next;
 
 	dpy = XOpenDisplay(0);

Modules/devinfo/devicelisting.cpp

@@ -140,7 +140,7 @@ void DeviceListing::itemActivatedSlot(QTreeWidgetItem *listItemIn ,const int col
   }
 }
 
-void DeviceListing::deviceAddedSlot(const QString udi) 
+void DeviceListing::deviceAddedSlot(const QString &udi)
 {  
   SolidHelper *solhelp = new SolidHelper();
   const QList<Solid::Device> list = Solid::Device::allDevices();

Modules/devinfo/devicelisting.h

@@ -61,7 +61,7 @@ class DeviceListing : public QTreeWidget
     DeviceListing(QWidget *, InfoPanel *, DevInfoPlugin *);
     ~DeviceListing();   
 
-    static QTreeWidgetItem *getTreeWidgetItemFromUdi(QTreeWidget *widget, QString udi)
+    static QTreeWidgetItem *getTreeWidgetItemFromUdi(QTreeWidget *widget, const QString &udi)
     {
         QTreeWidgetItemIterator treeWidget(widget);
 	while (*treeWidget) 
@@ -87,7 +87,7 @@ class DeviceListing : public QTreeWidget
     
   public Q_SLOTS:
     void itemActivatedSlot(QTreeWidgetItem *,const int);
-    void deviceAddedSlot(const QString);
+    void deviceAddedSlot(const QString &);
     void deviceRemovedSlot(const QString);
     void collapseAllDevicesSlot();
     void expandAllDevicesSlot();

Modules/opengl/opengl.cpp

@@ -203,7 +203,7 @@ static bool get_dri_device()
 		if (end2>end) end=end2;
 		dri_info.pci[end]='.';
 
-		QString cmd = QString("lspci -m -v -s ") + dri_info.pci;
+		QString cmd = QStringLiteral("lspci -m -v -s ") + dri_info.pci;
 		QStringList pci_info;
 		int num;
 		if (((num = ReadPipe(cmd, pci_info)) ||
@@ -537,8 +537,8 @@ print_limits(QTreeWidgetItem *l1, const char * glExtensions, bool getProcAddress
 		if (glGetError() == GL_NONE) {
 			QString s;
 			if (!tfloat && count == 1) s = QString::number(max[0]); else
-			if (!tfloat && count == 2) s = QString("%1, %2").arg(max[0]).arg(max[1]); else
-			if (tfloat && count == 2) s = QString("%1 - %2").arg(fmax[0],0,'f',6).arg(fmax[1],0,'f',6); else
+			if (!tfloat && count == 2) s = QStringLiteral("%1, %2").arg(max[0]).arg(max[1]); else
+			if (tfloat && count == 2) s = QStringLiteral("%1 - %2").arg(fmax[0],0,'f',6).arg(fmax[1],0,'f',6); else
 			if (tfloat && count == 1) s = QString::number(fmax[0],'f',6);
 			if (l3) l3 = newItem(l2, l3, cur_token->name, s);
 	 			else l3 = newItem(l2, cur_token->name, s);