Fix compilation with MSVC 2010

2013 and 2015 compile this fine. I didn't test 2012. I wouldn't have
fixed if the objective weren't to enable QtDBus by default on all
architectures: since it is, we can't have Qt fail to compile from
sources on MSVC 2010.

qdbus_symbols.cpp(92) : fatal error C1001: An internal error has
occurred in the compiler

Change-Id: I42b930bc37c4e478a66725d83c8a73836fbf567c
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@theqtcompany.com>
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>

src/dbus/qdbus_symbols.cpp

@@ -86,9 +86,9 @@ bool qdbus_loadLibDBus()
     static int majorversions[] = { 3, 2, -1 };
     const QString baseNames[] = {
 #ifdef Q_OS_WIN
-        QStringLiteral("dbus-1"),
+        QLatin1String("dbus-1"),
 #endif
-        QStringLiteral("libdbus-1")
+        QLatin1String("libdbus-1")
     };
 
     lib->unload();