Valgrind: Replace QDir::separator with slash

Change-Id: I8f8192dc065702cb1c6bb218b8d992bb9775cd10
Reviewed-by: hjk <hjk@theqtcompany.com>

src/plugins/valgrind/xmlprotocol/errorlistmodel.cpp

@@ -113,7 +113,7 @@ QString ErrorListModel::Private::formatAbsoluteFilePath(const Error &error) cons
 {
     const Frame f = findRelevantFrame(error);
     if (!f.directory().isEmpty() && !f.file().isEmpty())
-        return QString(f.directory() + QDir::separator() + f.file());
+        return f.directory() + QLatin1Char('/') + f.file();
     return QString();
 }