tools: utilize environment specific files for vsymlink

[ttytm]

To keep the review simpler this PR does an update of the current state prior to an extraction. Also, this can be good to have in the history.

The followup would be a structural update that allows for better organization and maintainability:

├── tools
│   ├── vsymlink
│   │   ├── vsymlink.v
│   │   ├── vsymlink_nix.c.v
│   │   └── vsymlink_windows.c.v
│   ├── ...

edit: Splitting the changes runs into some issues. To save some time, I'd directly include the extraction. The conceptual idea of the beforehand simplification would remain part of this PRs history.

[spytheman]

The tool is 210 lines on master, and is not going to change much in functionality. Only bug fixes for it will happen.

I do not see the value of splitting it into several files 🤔 .

[ttytm]

The tool is 210 lines on master, and is not going to change much in functionality. Only bug fixes for it will happen.

I do not see the value of splitting it into several files 🤔 .

It would make a direct distinction between the platform commands, and therefore the use of all the $if windows in the current file obsolete. Alternatively, if it's preferred to keep it in one file I'd just removing the anti-pattern of wrapping whole function bodies in if statements and reduce unnecessary nesting.

[spytheman]

All true, and yet, I feel a bit uneasy about splitting a 210 line file... Anyway that is a personal feeling, I'll get over it.

Good work.

[ttytm]

Thanks 👍