[llvm] [WindowsDriver] Always consider `WinSdkVersion` (PR #130377)

[Saleem Abdulrasool via llvm-commits]

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@@ -475,6 +482,12 @@ bool getUniversalCRTSdkDir(vfs::FileSystem &VFS,
           Path, nullptr))
     return false;
 
+  if (WinSdkVersion) {
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compnerd wrote:

The registry currently takes precedence here - should this not come before that? The only issue then remains is what if they specify `/winsdkdir` and `/winsdkversion`? I think that we should prefer to use the version requested against that SDK directory (or the default path if one is not specified).

https://github.com/llvm/llvm-project/pull/130377