[llvm] [DI] Have createClassType create a class type. (PR #102624)

[David Blaikie via llvm-commits]

dwblaikie wrote:

Yeah - if we didn't require test cases for fixes because the functionality was previously not tested - that'd mean not requiring any tests for any bug fixes, which would be weird, right? (we do require it, but sometimes we miss cases, or folks think it's trivial/doesn't need testing (I tend to not be aligned with that perspective, even simple things I tend to prefer having test coverage) 

Because I was curious if this was ever correct/how it regressed - and seems it regressed here: e274180f0efb5ff3358cf6076846b4cb326b2ed7

There is some unit test coverage for DIBuilder in llvm/unittests/IR/IRBuilderTest.cpp - so that's probably the place to add some coverage for this function, for instance.

https://github.com/llvm/llvm-project/pull/102624