[llvm] [ADT][APFloat] Make sure EBO is performed on APFloat (PR #111641)

[Matt Arsenault via llvm-commits]

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@@ -322,7 +322,38 @@ struct APFloatBase {
 
 namespace detail {
 
-class IEEEFloat final : public APFloatBase {
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arsenm wrote:

Most of these enums should probably move to enum class anyway 

https://github.com/llvm/llvm-project/pull/111641