[clang] [llvm] [mlir] [AArch64][llvm][clang] Remove `int_aarch64_sve_bfmmla` and reuse existing def (NFC) (PR #193970)

[Andrzej Warzyński via cfe-commits]

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@@ -294,10 +294,10 @@ def UsmmlaOp : ArmSVE_Op<"usmmla", [Pure,
     "$acc `,` $src1 `,` $src2 attr-dict `:` type($src1) `to` type($dst)";
 }
 
-def BfmmlaOp : ArmSVE_IntrOp<"bfmmla", [Pure,
-                                        AllTypesMatch<["src1", "src2"]>,
-                                        AllTypesMatch<["acc", "res"]>,
-                                        ]> {
+def BfmmlaOp : LLVM_IntrOpBase<ArmSVE_Dialect, "intr.bfmmla", "aarch64_sve_fmmla", [0], [1],
+                               [Pure,
+                                AllTypesMatch<["src1", "src2"]>,
+                                AllTypesMatch<["acc", "res"]>], 1> {
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banach-space wrote:

Why use `LLVM_IntrOpBase` directly? It's not immediately obvious to me that `ArmSVE_IntrOp` couldn't be re-used here. 

https://github.com/llvm/llvm-project/pull/193970