[llvm] [SPIR-V] Add SPIRV to LLVM_ALL_TARGETS (PR #119653)

[Michal Paszkowski via llvm-commits]

michalpaszkowski wrote:

Happy New Year! Thanks to everyone for all the comments!

> It looks like the SPIRV target currently lists @iliya-diyachkov as the maintainer (see https://github.com/llvm/llvm-project/blob/main/llvm/Maintainers.md#spirv-backend). However, I think they haven't been very involved in the past year (at least going by commit history). It would be great to update this to one or more people who are more actively involved right now. There should be plenty of candidates for this target, but you'll probably know better than I who to nominate here.
> 
> Edit: After a closer look, the commit history may be a bit misleading, as Ilia still occasionally does SPIRV code reviews, so maybe this information is less outdated than I initially thought. Would still be good to review :)

@nikic Thank you for reminding me about this! I asked @VyacheslavLevytskyy and @Keenuts to be maintainers. Slava is actively working on SYCL/DPC++ features and Nathan is focused on Vulkan/HLSL related changes (especially structurizer).

https://github.com/llvm/llvm-project/pull/119653