[clang] [llvm] [RISCV] Support spacemit vsmtvdotii extensions (PR #202533)

[Pengcheng Wang via cfe-commits]

================
@@ -96,6 +96,7 @@
 // CHECK-NEXT:     svinval              1.0       'Svinval' (Fine-Grained Address-Translation Cache Invalidation)
 // CHECK-NEXT:     svnapot              1.0       'Svnapot' (NAPOT Translation Contiguity)
 // CHECK-NEXT:     svpbmt               1.0       'Svpbmt' (Page-Based Memory Types)
+// CHECK-NEXT:     xsmtvdotii           1.0       'XSMTVDotII' (SpacemiT Vector Extension for Matrix(2.0))
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wangpc-pp wrote:

Does `2.0` need to surrounded  by brackets?
```suggestion
// CHECK-NEXT:     xsmtvdotii           1.0       'XSMTVDotII' (SpacemiT Vector Extension for Matrix 2.0)
```

https://github.com/llvm/llvm-project/pull/202533