[llvm] [GlobalISel] Don't treat intrinsic callbr indirect dest as machine successor. (PR #221685)

[Matt Arsenault via llvm-commits]

https://github.com/arsenm commented:

I don't understand what this is supposed to solve, but we don't really want the selector pass to be hacking up the CFG 

https://github.com/llvm/llvm-project/pull/221685