[clang] [CIR] Add x86_64 scalar calling-convention lowering (PR #209636)

[via cfe-commits]

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@@ -240,11 +240,19 @@ def CallConvLowering : Pass<"cir-call-conv-lowering", "mlir::ModuleOp"> {
   let dependentDialects = ["cir::CIRDialect"];
   let options = [
     Option<"target", "target", "std::string", /*default=*/"\"\"",
-           "Target whose ABI rules drive classification (currently: test)">,
+           "Target whose ABI rules drive classification (test, x86_64)">,
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adams381 wrote:

Made `target` an enum option with `clEnumValN`. No more name table or hand-parsing.


https://github.com/llvm/llvm-project/pull/209636