[llvm] [clang] [RISCV] Add support for Smepmp 1.0 (PR #78489)

[Craig Topper via cfe-commits]

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@@ -92,6 +92,7 @@ on support follow.
      ``M``            Supported
      ``Smaia``        Supported
      ``Ssaia``        Supported
+     ``Smepmp``       Supported
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topperc wrote:

I think this list is aphabetized.

https://github.com/llvm/llvm-project/pull/78489