[clang] [CIR] Upstream proper function alias lowering (PR #150520)

[Henrich Lauko via cfe-commits]

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@@ -257,6 +257,11 @@ class CIRToLLVMFuncOpLowering : public mlir::OpConversionPattern<cir::FuncOp> {
       cir::FuncOp func, bool filterArgAndResAttrs,
       mlir::SmallVectorImpl<mlir::NamedAttribute> &result) const;
 
+  mlir::LogicalResult
+  matchAndRewriteAlias(cir::FuncOp op, mlir::FlatSymbolRefAttr aliasee,
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xlauko wrote:

```suggestion
  matchAndRewriteAlias(cir::FuncOp op, llvm::StringRef aliasee,
```

https://github.com/llvm/llvm-project/pull/150520