[llvm] [OFFLOAD] Add JIT support for SPIRV backend (PR #212823)

[Joseph Huber via llvm-commits]

jhuber6 wrote:

Do we have a JIT test in the unit tests? We probably should, could just compile one of the device inputs as LLVM-IR instead of going to an object.

https://github.com/llvm/llvm-project/pull/212823