[llvm] [Offload] Implement the remaining initial Offload API (PR #122106)

[Joseph Huber via llvm-commits]

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@@ -16,8 +16,8 @@ def : Function {
     let details = [];
     let params = [
         Param<"ol_queue_handle_t", "Queue", "handle of the queue", PARAM_IN>,
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jhuber6 wrote:

Thanks, I think in the future we'll probably be able to get more out of this than just `memcpy`. Likely the whole host plugin should be moved into just 'the current device' and we move the 'plugins' which dlopen some code somewhere else. That should let us do things like enqueue host functions or something, but we can save that for later.

https://github.com/llvm/llvm-project/pull/122106