Ios端上传报错，0.7.0版本

[ToryCrox]

flutter: │ UMengApmSdk onError: Unsupported operation: Unsupported operating system., #0 notSupportedError (package:system_info2/src/utils.dart:124:3)
flutter: │ #1 getKernelName (package:system_info2/src/platform/kernel.dart:162:7)
flutter: │ #2 SysInfo.kernelName (package:system_info2/src/system_info.dart:38:36)
flutter: │ #3 SysInfo.kernelName (package:system_info2/src/system_info.dart)
flutter: │ #4 _getUserAgent (package:qiniu_sdk_base/src/storage/task/request_task.dart:12:46)
flutter: │ #5 RequestTask.preStart (package:qiniu_sdk_base/src/storage/task/request_task.dart:56:21)
flutter: │ #6 PutBySingleTask.preStart (package:qiniu_sdk_base/src/storage/methods/put/by_single/put_by_single_task.dart:33:11)
flutter: │ #7 TaskManager.addTask (package:qiniu_sdk_base/src/storage/task/task_manager.dart:16:11)
flutter: │ #8 RequestTaskManager.addTask (package:qiniu_sdk_base/src/storage/task/request_task_manager.dart:13:11)
flutter: │ #9 Storage.putFile (package:qiniu_sdk_base/src/storage/storage.dart:62:17)

[yunyun453162]

相同的报错，system_info2 4.0.0 上的这些个接口都不支持iOS

[zhangzqs]

这个问题在 #95 有顺带修复