Remove macro ANYARGS. It is not used in the core and bundled mrbgems. And it...

Remove macro ANYARGS. It is not used in the core and bundled mrbgems. And it is possible to conflict an application's macro.

include/mruby.h

@@ -340,13 +340,6 @@ typedef enum call_type {
     CALL_TYPE_MAX
 } call_type;
 
-#ifndef ANYARGS
-# ifdef __cplusplus
-#   define ANYARGS ...
-# else
-#   define ANYARGS
-# endif
-#endif
 void mrb_define_alias(mrb_state *mrb, struct RClass *klass, const char *name1, const char *name2);
 const char *mrb_class_name(mrb_state *mrb, struct RClass* klass);
 void mrb_define_global_const(mrb_state *mrb, const char *name, mrb_value val);