[Windows] Avoid using dirent.h @open sesame 01/15 12:44

[gkisalapl]

This PR start series of changes which should make possible compilation of nntrainer on windows platform.
Header dirent.h is not available on windows so to make code more portable I've replaced this functionality with std::filesystem

Self-evaluation:

1. Build test: [X]Passed [ ]Failed [ ]Skipped
2. Run test: [X]Passed [ ]Failed [ ]Skipped

[jijoongmoon]

@gkisalapl , Thanks for the PR. It is good if NNTrainer can support Windows Operating System naturally and I'm sure you are working on it. Thanks aging. One thing I want to address is that this Windows Porting task shouldn't be only for windows. I mean this code change also should work in other platform such as android, Linux, etc. So It might be better to use separate build processes, files and defines.

[DonghakPark]

LGTM!
i will check CI unable to access 'https://github.com/nnstreamer/nntrainer/': The requested URL returned error: 503 it seems like github access error

[gkisalapl]

@gkisalapl , Thanks for the PR. It is good if NNTrainer can support Windows Operating System naturally and I'm sure you are working on it. Thanks aging. One thing I want to address is that this Windows Porting task shouldn't be only for windows. I mean this code change also should work in other platform such as android, Linux, etc. So It might be better to use separate build processes, files and defines.

Yes I'm making those changes in the way it works both on windows and linux/android. Draft PR with experimental windows build is exception here - I've focused on proof of concept windows build in this draft PR.

[DonghakPark]

Please use rebase command

git rebase upstream/main

[gkisalapl]

Please use rebase command

git rebase upstream/main

I've broke rebase operation and create new PR with manual rebase of those changes on top of current main #2884