[llvm] Add Zstandard to Windows release build (PR #186772)

[Aiden Grossman via llvm-commits]

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@@ -149,6 +149,9 @@ if "%skip-checkout%" == "true" (
 curl -O https://gitlab.gnome.org/GNOME/libxml2/-/archive/v2.9.12/libxml2-v2.9.12.tar.gz || exit /b 1
 tar zxf libxml2-v2.9.12.tar.gz
 
+curl -O https://github.com/facebook/zstd/releases/download/v1.5.7/zstd-1.5.7.tar.gz || exit /b 1
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boomanaiden154 wrote:

We should probably be verifying a SHA for this file.

https://github.com/llvm/llvm-project/pull/186772