[clang] [llvm] [mlir] [lld] [AMDGPU] Change default AMDHSA Code Object version to 5 (PR #73000)

[Jon Chesterfield via cfe-commits]

JonChesterfield wrote:

This is a wild amount of code churn from a trivial change. 10k lines of almost all noise. Means the chances of us noticing breakage in a code review tool is pretty low.

How about as a first patch we pass `-code-object=v4` or whatever syntax to essentially all the tests, then rebase this, so that we can get something approximating "this is the functional change, with the codegen change visible in these tests"?

In general it seems likely that a lot of tests are checking things they don't actually care about, probably because they're frequently generated by the python thing. Maybe some of the noise can be removed by tweaking the test generator script to emit checks that are insensitive to ABI version?

https://github.com/llvm/llvm-project/pull/73000