!4718 【OpenHarmony开源贡献者计划2022】driver-platform-gpio-des.md中取消中断示例拼写错误

Merge pull request !4718 from hgv5/modify-gpio

zh-cn/device-dev/driver/driver-platform-gpio-des.md

@@ -302,7 +302,7 @@ static int32_t TestCaseGpioIrqEdge(void)
     ret = GpioEnableIrq(gpio);
     if (ret != HDF_SUCCESS) {
         HDF_LOGE("%s: enable irq fail! ret:%d\n", __func__, ret);
-        (void)GpioUnSetIrq(gpio);
+        (void)GpioUnsetIrq(gpio, NULL);
         return ret;
     }