[clang] [RISCV] Fix wrong implication for zvknhb. (PR #66860)

[Jianjian Guan via cfe-commits]

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@@ -599,15 +599,21 @@ def HasStdExtZvkned : Predicate<"Subtarget->hasStdExtZvkned()">,
 def FeatureStdExtZvknha
     : SubtargetFeature<"experimental-zvknha", "HasStdExtZvknha", "true",
                        "'Zvknha' (Vector SHA-2 (SHA-256 only))">;
-
-def FeatureStdExtZvknhb
-    : SubtargetFeature<"experimental-zvknhb", "HasStdExtZvknhb", "true",
-                       "'Zvknhb' (Vector SHA-2 (SHA-256 and SHA-512))",
-                       [FeatureStdExtZvknha]>;
 def HasStdExtZvknha : Predicate<"Subtarget->hasStdExtZvknha()">,
                                 AssemblerPredicate<(all_of FeatureStdExtZvknha),
                                 "'Zvknha' (Vector SHA-2 (SHA-256 only))">;
 
+def FeatureStdExtZvknhb
+    : SubtargetFeature<"experimental-zvknhb", "HasStdExtZvknhb", "true",
+                       "'Zvknhb' (Vector SHA-2 (SHA-256 and SHA-512))">;
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jacquesguan wrote:

I think that Zvknhb requires Zve64x

https://github.com/llvm/llvm-project/pull/66860