[clang] [llvm] [RISCV][MC] Implement MC for Base P extension (PR #123271)

[Kito Cheng via llvm-commits]

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@@ -335,6 +335,9 @@ The primary goal of experimental support is to assist in the process of ratifica
 ``experimental-svukte``
   LLVM implements the `0.3 draft specification <https://github.com/riscv/riscv-isa-manual/pull/1564>`__.
 
+``experimental-p``, ``experimental-p``
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kito-cheng wrote:

```suggestion
``experimental-p``,
```

https://github.com/llvm/llvm-project/pull/123271