[llvm] [TableGen][Docs] Fix productionlists for assert and dump (PR #123739)

[Akshat Oke via llvm-commits]

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@@ -1302,7 +1302,7 @@ output. It is intended for debugging purpose.
   instantiation point of the containing record.
 
 .. productionlist::
-   Dump: "dump"  `string` ";"
+   Dump: "dump" `Value` ";"
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optimisan wrote:

Yes, this seems better.

A subtlety is that even record types are accepted by `dump` (it silently wraps them in `!repr`), but I'm not sure if we should advertise that as well.

https://github.com/llvm/llvm-project/pull/123739