[llvm] On Windows, make the release script work with the local git checkout (PR #78273)

[via llvm-commits]

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@@ -7,14 +7,16 @@ goto begin
 echo Script for building the LLVM installer on Windows,
 echo used for the releases at https://github.com/llvm/llvm-project/releases
 echo.
-echo Usage: build_llvm_release.bat --version ^<version^> [--x86,--x64, --arm64]
+echo Usage: build_llvm_release.bat --version ^<version^> [--x86,--x64, --arm64] [--skip-checkout] [--local-python]
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zmodem wrote:

I see it used on line 372.

https://github.com/llvm/llvm-project/pull/78273