[clang] [CLANG]Add Scalable vectors for mfloat8_t (PR #101644)

[Paul Walker via cfe-commits]

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@@ -87,6 +87,10 @@ class SVEType {
   bool isDefault() const { return DefaultType; }
   bool isFloat() const { return Float && !BFloat; }
   bool isBFloat() const { return BFloat && !Float; }
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paulwalker-arm wrote:

To be consistent I think these need updating to include `&& !MFloat`?

There's also an "isFloatingPoint()" method that probably needs `|| MFloat`.

https://github.com/llvm/llvm-project/pull/101644