[clang] [Clang] Amend SME attributes with support for ZT0. (PR #77941)

[Erich Keane via cfe-commits]

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@@ -4253,7 +4260,7 @@ class FunctionProtoType final
     FunctionType::ExtInfo ExtInfo;
     unsigned Variadic : 1;
     unsigned HasTrailingReturn : 1;
-    unsigned AArch64SMEAttributes : 6;
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erichkeane wrote:

Note that thanks to bitfield packing, this is expanding this struct an entire byte.

https://github.com/llvm/llvm-project/pull/77941