qmldump: Always check for private headers being available

4.7.1 won't come with private headers always being installed.

Reviewed-by: ckamm

src/plugins/qt4projectmanager/qmldumptool.cpp

@@ -131,7 +131,7 @@ bool QmlDumpTool::canBuild(const QtVersion *qtVersion)
     const QString installHeaders = qtVersion->versionInfo().value("QT_INSTALL_HEADERS");
     const QString header = installHeaders + QLatin1String("/QtDeclarative/private/qdeclarativemetatype_p.h");
     return qtVersion->supportsTargetId(Constants::DESKTOP_TARGET_ID)
-            && (checkMinimumQtVersion(qtVersion->qtVersionString(), 4, 7, 1) || QFile::exists(header));
+            && QFile::exists(header);
 }
 
 static QtVersion *qtVersionForProject(ProjectExplorer::Project *project)