Reverts nim-lang/Nim#25090
It seems to cause problems for C++ and i686
```
2025-08-08T02:37:55.5976232Z c:/a/nightlies/nightlies/external/mingw32/bin/../lib/gcc/i686-w64-mingw32/11.1.0/../../../../i686-w64-mingw32/bin/ld.exe: C:\Users\runneradmin\nimcache\manual_experimental_snippet_106_d\@pstd@sprivate@ssyslocks.nim.c.o:@pstd@sprivate@ssyslocks.nim.c:(.text+0x29): undefined reference to `SleepConditionVariableCS'
2025-08-08T02:37:55.5978066Z c:/a/nightlies/nightlies/external/mingw32/bin/../lib/gcc/i686-w64-mingw32/11.1.0/../../../../i686-w64-mingw32/bin/ld.exe: C:\Users\runneradmin\nimcache\manual_experimental_snippet_106_d\@pthreadpool.nim.c.o:@pthreadpool.nim.c:(.text+0x26): undefined reference to `InitializeConditionVariable'
2025-08-08T02:37:55.5980101Z c:/a/nightlies/nightlies/external/mingw32/bin/../lib/gcc/i686-w64-mingw32/11.1.0/../../../../i686-w64-mingw32/bin/ld.exe: C:\Users\runneradmin\nimcache\manual_experimental_snippet_106_d\@pthreadpool.nim.c.o:@pthreadpool.nim.c:(.text+0x116): undefined reference to `WakeConditionVariable'
2025-08-08T02:37:55.5981093Z collect2.exe: error: ld returned 1 exit status
2025-08-08T02:37:55.5988564Z Error: execution of an external program failed: 'gcc.exe -o
```
