windows: Delete obsolete environment variable kernel32 wrappers and bindings
These functions have been unused for a long time (since cfffb9c5e96eeeae43cd724e2d02ec8c2b7714e0; the PEB is used for this stuff now), and the GetEnvironmentVariableW wrapper's parameter types don't make much sense to boot.
Contributes towards:
- https://github.com/ziglang/zig/issues/4426
- https://github.com/ziglang/zig/issues/1840
8709326088Ryan Liptak committed on 6/2/2025, 8:34:37 AM· committed by Alex Rønne Petersenparentfa80737