[clang] [clang][bytecode] Unify elementwise integer builtins using callback pattern (PR #169957)

[Simon Pilgrim via cfe-commits]

RKSimon wrote:

I think you're ok. A good quick check is to see if the buildbot went green again in the following build. Some of the bots can be intermittent.

https://github.com/llvm/llvm-project/pull/169957