[clang] Revise the modules document for clarity (PR #90237)

[Erich Keane via cfe-commits]

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@@ -530,43 +527,43 @@ Now the linkage name of ``NS::foo()`` will be ``_ZN2NS3fooEv``.
 Module Initializers
 ~~~~~~~~~~~~~~~~~~~
 
-All the importable module units are required to emit an initializer function.
-The initializer function should contain calls to importing modules first and
-all the dynamic-initializers in the current module unit then.
-
-Translation units explicitly or implicitly importing named modules must call
-the initializer functions of the imported named modules within the sequence of
-the dynamic-initializers in the TU. Initializations of entities at namespace
-scope are appearance-ordered. This (recursively) extends into imported modules
-at the point of appearance of the import declaration.
+All importable module units are required to emit an initializer function. The
----------------
erichkeane wrote:

```suggestion
All importable module units are required to emit an initializer function to handle <what?>. The
```

ARE they required, or only if there is some sort of static initialization happening in the module?

https://github.com/llvm/llvm-project/pull/90237