WasmEdge [Docs] Rearrange and rephrase buld instructions

Just made a few rearrangements and added a link.

Sep 09 '22 07:09 abhinandanudupa

# Download our pre-built LLVM 13 binary
$llvm = "LLVM-13.0.1-win64.zip"
curl -sLO https://github.com/WasmEdge/llvm-windows/releases/download/llvmorg-13.0.1/LLVM-13.0.1-win64.zip -o $llvm
Expand-Archive -Path $llvm

https://wasmedge.org/book/en/extend/build_on_windows.html#prepare-the-environment @hydai We should be removing the part where we are downloading clang. Downloading the pre-built LLVM is not ideal as users will have to fix an issue related to #1290. Let the users download LLVM and clang with Visual Studio itself. Should I remove this part and add instructions to install from Visual Studio?

Sep 12 '22 03:09 abhinandanudupa

Sure, the previous steps are using in our CI. It's fine to use the VS one.

Sep 12 '22 03:09 hydai

Ok, will do it then.

Sep 12 '22 03:09 abhinandanudupa

I raised this PR with the intention of updating it to use LLVM 14 assuming that the LLVM from Visual Studio is being used in the CI and locally. But it turns out that that is not the case as not specifying the directory to the downloaded LLVM 13 will result in the build system asking for a path to LLVM - as tested locally. Hence it is not useful to continue with the PR - until we use LLVM 14.

Sep 22 '22 16:09 abhinandanudupa

Hi @abhinandanudupa

It's totally fine to use any version of LLVM including 12, 13, 14, and 15. You can use the latest version from the VS's one.

Sep 22 '22 17:09 hydai

Ok, then I will find a way to use the built-in version from Visual Studio.

Sep 22 '22 17:09 abhinandanudupa