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

[Callum Fare via llvm-commits]

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@@ -34,6 +34,69 @@ struct ol_platform_handle_t_ {
   std::vector<ol_device_handle_t_> Devices;
 };
 
+struct ol_queue_handle_t_ {
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callumfare wrote:

I've changed this to `ol_*_queue_impl_t`

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