Addresses the issues found on the review of
https://github.com/llvm/llvm-project/pull/150267/files#r2356936355
Currently when collecting the users of an IFunc symbol to determine the
callers, we incorrectly mix versions of different functions together,
alongside non-FMV callers all in the same bag. That is problematic
because we incorrectly deduce which features are unavailable as we
iterate the callers.
I have updated the unit tests to require a resolver function for the
callers and regenerated the resolvers since some FMV features have been
removed making the detection bitmasks different. I've replaced the
deleted FMV feature ls64 with cssc. I've added a new test to cover
unrelated callers.
3add3abd53