[llvm] [SPIRV] Addition of extension SPV_KHR_non_semantic_info and SPV_KHR_relaxed_extended_instruction (PR #165302)

[Nathan Gauër via llvm-commits]

Keenuts wrote:

> Have added the extension SPV_KHR_relaxed_extended_instructions for the instructions @Keenuts.

This PR seem to refactorize a bit the existing code and adds a lot of new bits.
Would it be possible to make it more reviewer-friendly by:
 - having an initial PR doing the rafactoring of the current EmitNonSemanticDI file
 - then small PRs adding one or a few similar debug instructions bit by bit (those should be non-controversial once the first has been merged)

https://github.com/llvm/llvm-project/pull/165302