1、修复新建商城订单时积分兑换报错的缺陷；

controller/mall.go

@@ -270,7 +270,7 @@ func MallOrderCreate(c *gin.Context) {
 
 	totalRm := (combo.PriceRm*req.Quantity*discount + 5) / model.Rmb
 	couponDiscount := userCoupon.Value
-	if totalRm <= couponDiscount {
+	if totalRm < couponDiscount {
 		log.Error().Msgf("coupon value[%d] is err, code is:", couponDiscount, req.CouponCode)
 		RespJson(c, status.InternalServerError, nil)
 		return