[clang] [llvm] [DXIL] implement dot intrinsic lowering for integers (PR #85662)

[Farzon Lotfi via cfe-commits]

farzonl wrote:

@nico @dyung @llvm-beanz  this pr should fix the build break: https://github.com/llvm/llvm-project/pull/85839/files

https://github.com/llvm/llvm-project/pull/85662