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

[Arthur Eubanks via cfe-commits]

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@@ -57,6 +57,16 @@ 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 use a different code model for
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aeubanks wrote:

Something like
```
The ``model`` attribute allows overriding the translation unit's code model (specified by ``-mcmodel``) for a specific global variable.
```
is clearer

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