Use new specifiers/modifiers of `mrb_vfromat()`

The binary sizes (gems are only `mruby-bin-mruby`) are reduced slightly in
my environment than before the introduction of new specifiers/modifiers
(5116789a) with this change.

  ------------+-------------------+-------------------+--------
   BINARY     | BEFORE (5116789a) |   AFTER (This PR) |  RATIO
  ------------+-------------------+-------------------+--------
   mruby      |      593416 bytes |      593208 bytes | -0.04%
   libmruby.a |      769048 bytes |      767264 bytes | -0.23%
  ------------+-------------------+-------------------+--------

BTW, I accidentally changed `tasks/toolchains/visualcpp.rake` at #4613,
so I put it back.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/range.c b/src/range.c
index c9dfb2b3c..28862d779 100644
--- a/src/range.c
+++ b/src/range.c
@@ -363,7 +363,7 @@ mrb_get_values_at(mrb_state *mrb, mrb_value obj, mrb_int olen, mrb_int argc, con
       }
     }
     else {
-      mrb_raisef(mrb, E_TYPE_ERROR, "invalid values selector: %S", argv[i]);
+      mrb_raisef(mrb, E_TYPE_ERROR, "invalid values selector: %v", argv[i]);
     }
   }