message: Clarify documentation for GinkgoIterativeSolver base class
diff: @@ -581,8 +581,9 @@ protected:
  };
  /**
  -* This class forms the base class for all of Ginkgo's iterative solvers. The
  -* various derived classes only take the additional data that is specific to them
  +* This class forms the base class for all of Ginkgo's iterative solvers.
  +* It is not intended to be used directly by MFEM applications. The various
  +* derived classes only take the additional data that is specific to them
  * and solve the given linear system. The entire collection of solvers that
  * Ginkgo implements is available at the Ginkgo documentation and manual pages,
  * https://ginkgo-project.github.io/ginkgo/doc/develop.
  @@ -596,6 +597,11 @@ public:
  * Constructor.
  *
  * The @p exec defines the paradigm where the solution is computed.
  + * @p use_implicit_res_norm is for internal use by the derived classes
  + * for specific Ginkgo solvers; it indicates whether the solver makes
  + * an implicit residual norm estimate available for convergence checking.
  + * Each derived class automatically sets the correct value when calling this
  + * base class constructor.
  *
  */
  GinkgoIterativeSolver(GinkgoExecutor &exec, int print_iter,
  