Fixed a bug in NCMesh::GetDerefinementTransforms in case of no derefinements (we still want the identity matrix).
Fixed a bug in NCMesh::GetDerefinementTransforms in case of no derefinements (we still want the identity matrix).

mfem/mfem,mfem/mfem,mfem/mfem,mfem/mfem,mfem/mfem