fix ANSI pathname under windows

[kbkpbot]

fix #21502

This PR will make compile non-English pathname/filename under Windows possible.
For example:

v D:\测试目录\测试.v
测试.exe

[kbkpbot]

Should encoding.iconv support a special encoding LOCAL? This encoding will be 'ANSI' under Windows, and 'UTF-8' under Linux.

This will simplify some codes.

[JalonSolov]

I think a common name would be good, so you don't have to add the extra logic to decide based on the target OS when you compile.