message: Try to suppress deprecation warning with GCC from the
  `IterativeSolver` constructors.
diff: @@ -125,7 +125,7 @@ protected:
  /** @brief (DEPRECATED) Legacy print level definition, which is left for
  compatibility with custom iterative solvers.
  @deprecated #print_options should be used instead. */
  - MFEM_DEPRECATED int print_level = -1;
  + MFEM_DEPRECATED int print_level;
  /** @brief Output behavior for the iterative solver.
  