[llvm] [SPIR-V] Built-in variables: mapping from an OpenCL to SPIR-V BuiltIn and SPIR-V friendly builtins for Image Read/Write instructions (PR #127242)

[Vyacheslav Levytskyy via llvm-commits]

VyacheslavLevytskyy wrote:

This PR should also help to improve builtins representation on client sides: see https://github.com/llvm/llvm-project/pull/126111 for the dicsussion.

https://github.com/llvm/llvm-project/pull/127242