bug fix for q=3

Mesh/HighOrder.cpp

@@ -628,6 +628,7 @@ void getFaceVertices(GFace *gf, MElement *ele, std::vector<MVertex*> &vf,
 
 void reorientTrianglePoints(std::vector<MVertex*>& vtcs,int orientation,bool swap) {
 
+  if (vtcs.size() == 1) return;
   
   size_t nbPts = vtcs.size();