[llvm] [AMDGPU] Allow lane-op lowering for some illegal types (PR #114887)

[Stanislav Mekhanoshin via llvm-commits]

rampitec wrote:

> What's the point of handling i1/i8?

Clang can produce intrinsic with char argument out of builtin. Will be able after https://github.com/llvm/llvm-project/pull/115090.

https://github.com/llvm/llvm-project/pull/114887