add similar range check for tm->usec as well

mrbgems/mruby-time/src/time.c

@@ -685,11 +685,9 @@ mrb_time_usec(mrb_state *mrb, mrb_value self)
   struct mrb_time *tm;
 
   tm = DATA_GET_PTR(mrb, self, &mrb_time_type, struct mrb_time);
-#ifdef MRB_INT16
   if (tm->usec > MRB_INT_MAX || tm->usec < MRB_INT_MIN) {
     return mrb_float_value(mrb, (mrb_float)tm->usec);
   }
-#endif
   return mrb_fixnum_value((mrb_int)tm->usec);
 }