[clang] [OpenMP] Allow GPUs to be targeted directly via `-fopenmp`. (PR #122149)

[Joseph Huber via cfe-commits]

jhuber6 wrote:

> ~I don't think it should be GPU code generation path as there is no explicit `target` region used.~ Probably I missed something here. Do you expect regular OpenMP stuff such as `parallel` region to be emitted in the same way as offloading code?

Yes, the example in the description is how I can see this being used. It basically lets us emit GPU code without the build system complications introduced by offloading languages (i.e. we no longer need variants or declare target.)

https://github.com/llvm/llvm-project/pull/122149