message: Fix nvcc virtual function warnings
diff: @@ -1268,6 +1268,7 @@ public:
  virtual void Eval(DenseSymmetricMatrix &K, ElementTransformation &T,
  const IntegrationPoint &ip) = 0;
  + using MatrixCoefficient::Eval;
  /** @brief Evaluate the matrix coefficient in the element described by @a T
  at the point @a ip, storing the result as a dense matrix @a K. */
  /** This function allows the use of SymmetricMatrixCoefficient in situations
  @@ -1293,6 +1294,7 @@ public:
  ///Construct using matrix @a m for the constant.
  SymmetricMatrixConstantCoefficient(const DenseSymmetricMatrix &m)
  : SymmetricMatrixCoefficient(m.Height()), mat(m) { }
  + using MatrixCoefficient::Eval;
  using SymmetricMatrixCoefficient::Eval;
  /// Evaluate the matrix coefficient at @a ip.
  virtual void Eval(DenseSymmetricMatrix &M, ElementTransformation &T,
  @@ -1344,6 +1346,8 @@ public:
  /// Set the time for internally stored coefficients
  void SetTime(double t);
  + using MatrixCoefficient::Eval;
  + using SymmetricMatrixCoefficient::Eval;
  /// Evaluate the matrix coefficient at @a ip.
  virtual void Eval(DenseSymmetricMatrix &K, ElementTransformation &T,
  const IntegrationPoint &ip);
  