[llvm] [llvm-shlib] Fix the version naming style of libLLVM for Windows (PR #85710)

[via llvm-commits]

llvmbot wrote:

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Failed to cherry-pick: cb2ca23345d3d9bde027a18d301949e8bdf606a6

https://github.com/llvm/llvm-project/actions/runs/8338749880

Please manually backport the fix and push it to your github fork.  Once this is done, please create a [pull request](https://github.com/llvm/llvm-project/compare)

https://github.com/llvm/llvm-project/pull/85710