[clang] [CIR][NFCI] Refactor uses of 'mlir::Location' vs 'SourceRange' on calls/etc (PR #222981)

[Andy Kaylor via cfe-commits]

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andykaylor wrote:

```suggestion
    cgm.errorNYI(loc, "emitScalarInit: captured by init");
```
Would this be a more accurate location? There are a couple of places where this is called with a decl location.

https://github.com/llvm/llvm-project/pull/222981