And return ENOSYS. We do that so we can at least compile the code on CI.
We'll be gradually enabling more and more functions.
Also, enabled `proc_raise()` for windows.
This folder contains the platform abstract layer for multiple platforms. To support a new platform, you can simply create a new folder here and implement all the APIs defined in include folder.
Refer to port_wamr.md for how to port WAMR to a target platform.