[clang] [Clang][SME] Add IsStreamingOrSVE2p1 (PR #76975)

[David Spickett via cfe-commits]

================
@@ -50,6 +50,7 @@ class LLVM_LIBRARY_VISIBILITY AArch64TargetInfo : public TargetInfo {
   bool HasMatMul = false;
   bool HasBFloat16 = false;
   bool HasSVE2 = false;
+  bool HasSVE2p1 = false;
----------------
DavidSpickett wrote:

FYI
```
/home/david.spickett/llvm-project/clang/lib/Basic/Targets/AArch64.h:53:8: warning: private field 'HasSVE2p1' is not used [-Wunused-private-field]
  bool HasSVE2p1 = false;
       ^
1 warning generated.
```


https://github.com/llvm/llvm-project/pull/76975