add missing std moves

code/AssetLib/DXF/DXFLoader.cpp

@@ -57,6 +57,7 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include <assimp/importerdesc.h>
 
 #include <numeric>
+#include <utility>
 
 using namespace Assimp;
 
@@ -150,7 +151,7 @@ void DXFImporter::InternReadFile( const std::string& filename, aiScene* pScene,
     // DXF files can grow very large, so read them via the StreamReader,
     // which will choose a suitable strategy.
     file->Seek(0,aiOrigin_SET);
-    StreamReaderLE stream( file );
+    StreamReaderLE stream( std::move(file) );
 
     DXF::LineReader reader (stream);
     DXF::FileData output;