[llvm] [utils] Add script to generate elaborated assembly tests (PR #89026)

[Fangrui Song via llvm-commits]

MaskRay wrote:

> probably worth a discourse post to get some feedback/visibility - but yeah, reckon it'd be a handy utility, similarly for LLVM IR debug info tests.

Posted it 2 days ago:)

> Link: [discourse.llvm.org/t/utility-to-generate-elaborated-assembly-ir-tests/78408](https://discourse.llvm.org/t/utility-to-generate-elaborated-assembly-ir-tests/78408)



https://github.com/llvm/llvm-project/pull/89026