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

[David Spickett via cfe-commits]

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@@ -32,7 +32,7 @@ extern "C" {
 #define __isb(i) __builtin_arm_isb(i)
 #endif
 
-/* 8.4 Hints */
+/* 7.4 Hints */
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DavidSpickett wrote:

If we're matching the section titles then they should have the extra `.` on the end of the number, so here `7.4. Hints`. Just to make searching more obvious.

Though in Firefox and Chrome they struggled to find it but that's down to the HTML formatting I think. At least visually it'll match up.

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