Fix typo in backward compatible mrb_exc_new_str_lit() macro

include/mruby/error.h

@@ -24,7 +24,7 @@ struct RException {
 MRB_API void mrb_sys_fail(mrb_state *mrb, const char *mesg);
 MRB_API mrb_value mrb_exc_new_str(mrb_state *mrb, struct RClass* c, mrb_value str);
 #define mrb_exc_new_lit(mrb, c, lit) mrb_exc_new_str(mrb, c, mrb_str_new_lit(mrb, lit))
-#define mrb_exc_new_str_lit(mrb, c, lit) mrb_exc_new_str_lit(mrb, c, lit)
+#define mrb_exc_new_str_lit(mrb, c, lit) mrb_exc_new_lit(mrb, c, lit)
 MRB_API mrb_value mrb_make_exception(mrb_state *mrb, mrb_int argc, const mrb_value *argv);
 MRB_API mrb_value mrb_exc_backtrace(mrb_state *mrb, mrb_value exc);
 MRB_API mrb_value mrb_get_backtrace(mrb_state *mrb);