[llvm] [TableGen][NFC] Remove MultiClass argument and Scoper in QualifyName (PR #69297)

[Nicolai Hähnle via llvm-commits]

https://github.com/nhaehnle approved this pull request.

LGTM, but see the inline suggestion.

I wonder if `Record` should have an IsMulticlass field to avoid the need for the IsMC boolean argument?

https://github.com/llvm/llvm-project/pull/69297