[clang] [RISCV][sema] Correct the requirement of `vf[|n|w]cvt.f.*` intrinsics (PR #101608)

[Brandon Wu via cfe-commits]

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@@ -1912,8 +1912,12 @@ def vfcvt_rtz_x_f_v : RVVConvToSignedBuiltin<"vfcvt_rtz_x">;
 let Log2LMUL = [-3, -2, -1, 0, 1, 2] in {
   def vfwcvt_rtz_xu_f_v : RVVConvToWidenUnsignedBuiltin<"vfwcvt_rtz_xu">;
   def vfwcvt_rtz_x_f_v : RVVConvToWidenSignedBuiltin<"vfwcvt_rtz_x">;
-  def vfwcvt_f_xu_v : RVVConvBuiltin<"Fw", "FwUv", "csi", "vfwcvt_f">;
-  def vfwcvt_f_x_v : RVVConvBuiltin<"Fw", "Fwv", "csi", "vfwcvt_f">;
+  def vfwcvt_f_xu_v : RVVConvBuiltin<"Fw", "FwUv", "si", "vfwcvt_f">;
+  def vfwcvt_f_x_v : RVVConvBuiltin<"Fw", "Fwv", "si", "vfwcvt_f">;
+  let RequiredFeatures = ["Zvfh"], OverloadedName = "vfwcvt_f" in {
+    defm : RVVConvBuiltinSet<"vfwcvt_f_xu_v", "c", [["Fw", "FwUv"]]>;
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4vtomat wrote:

`Name`, `IRName`, `MaskedIRName` uses `NAME` which is the defining name as default, but "si" case already used for defining name, if we use the same name for defining the "c" case, it would be multiple definition.

https://github.com/llvm/llvm-project/pull/101608