[llvm] [SPIRV] Change how to detect OpenCL/Vulkan Env and update tests accordingly. (PR #129689)

[Marcos Maronas via llvm-commits]

maarquitos14 wrote:

> > @Keenuts friendly ping
> 
> Sorry, missed your notification You mean we have tests using `spirv-unknown-unknown` for Vulkan? If so, yes I don't see any issues with updating those to have the explicit `vulkan` env bit

Yes, that's what I meant. I'll update those and ping again when the CI is green to make sure we are on the same page.

https://github.com/llvm/llvm-project/pull/129689