[clang] [NFC][Clang][Headers] Update refs to ACLE in comments (PR #66662)

[Kristof Beyls via cfe-commits]

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@@ -20,8 +20,8 @@
 extern "C" {
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kbeyls wrote:

Thanks, all of these updates look correct to me.
Since these all refer to sections in a document, I think it may be useful too to add a hyperlink at the top of the document to where the ACLE lives.
I think the correct hyperlink would be https://github.com/ARM-software/acle/releases/.

@vhscampos Do you think that would be a good idea too?

https://github.com/llvm/llvm-project/pull/66662