[clang] [CLANG][AArch64] Add the modal 8 bit floating-point scalar type (PR #97277)

[Paul Walker via cfe-commits]

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@@ -700,6 +701,9 @@ class TargetInfo : public TransferrableTargetInfo,
     return HasBFloat16 || HasFullBFloat16;
   }
 
+  /// Determine whether the _mfp8 type is supported on this target.
+  virtual bool hasArmMFloat8Type() const { return HasMFloat8; }
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paulwalker-arm wrote:

Do we want to be this strict when it comes to using the type?  Typically we don't hide the types behind feature flags anymore because it can make them more awkward to us.  For example, a function declaration referencing `mfloat8_t*` would fail to compiler despite not requiring an fp8 features.

https://github.com/llvm/llvm-project/pull/97277