[llvm] [InstCombine] Prevent i8 canonicalize for SPIR-V (PR #147527)

[Nikita Popov via llvm-commits]

https://github.com/nikic requested changes to this pull request.

This is something you need to handle in the SPIRV backend. This type information will cease to exist in the future.

https://github.com/llvm/llvm-project/pull/147527