[llvm] Fix for logic in combineExtract() (PR #108208)

[Jonas Paulsson via llvm-commits]

JonPsson1 wrote:

I guess I am a little confused here as to the lack of the bytevector check for BITCAST inside combineExtract(). Couldn't it at least in theory be that - as this is in a loop - there are more BITCASTs reached which could then involve i1 vectors? 

https://github.com/llvm/llvm-project/pull/108208