[clang] [clang] Add per-global code model attribute (PR #72078)

[WÁNG Xuěruì via cfe-commits]

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@@ -57,6 +57,15 @@ global variable or function should be in after translation.
   let Heading = "section, __declspec(allocate)";
 }
 
+def CodeModelDocs : Documentation {
+  let Category = DocCatVariable;
+  let Content = [{
+The ``model`` attribute allows you to specify a specific code model a
+global variable should be in after translation.
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xen0n wrote:

"allows you to override the code model that accesses to the decorated global variable should be in"? Or something similar to the GCC docs for the attribute.

https://github.com/llvm/llvm-project/pull/72078