[llvm] [llvm-readelf] Update outdated URL (PR #120498)

[James Henderson via llvm-commits]

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@@ -127,9 +127,11 @@ enum {
 // Versioning
 enum { EV_NONE = 0, EV_CURRENT = 1 };
 
-// Machine architectures
-// See current registered ELF machine architectures at:
-//    http://www.uxsglobal.com/developers/gabi/latest/ch4.eheader.html
+// Machine architectures.
+// At the time of writing, the list of registered machine architectures is
+// at https://groups.google.com/g/generic-abi/c/0kORSDcyhTE/m/ZRf_PvcHAAAJ
+// Please refer to https://groups.google.com/g/generic-abi for any further
+// updates
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jh7370 wrote:

Nit: please add a trailing "." here - LLVM comments should be full sentences and always end in a period, per the style guide.

https://github.com/llvm/llvm-project/pull/120498