[llvm] [VectorCombine] Add Ext and Trunc support in foldBitOpOfCastConstant (PR #157822)

[Rajveer Singh Bharadwaj via llvm-commits]

https://github.com/Rajveer100 commented:

We could use splat for cases like these for better visibility:

```llvm
%u.masked = and <16 x i32> %u, <i32 255, i32 255, i32 255, i32 255, i32 255, i32 255, i32 255, i32 255, i32 255, i32 255, i32 255, i32 255, i32 255, i32 255, i32 255, i32 255>
```

https://github.com/llvm/llvm-project/pull/157822