[llvm] [OFFLOAD] Add missing interop API for libomptarget migration (PR #172951)

[Shilei Tian via llvm-commits]

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@@ -1214,5 +1214,58 @@ Error olLaunchHostFunction_impl(ol_queue_handle_t Queue,
                                                 Queue->AsyncInfo);
 }
 
+Error olCreateInterop_impl(ol_device_handle_t Device, int32_t InteropContext, void *InteropSpec,
+                           void **Interop) {
+  auto Rc = Device->Device->createInterop(InteropContext, 
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shiltian wrote:

The entire interop concept should stay in OpenMP because it is an OpenMP concept, instead of a `liboffload` one. When OpenMP needs to interop with device, sure, get/do it from liboffload.

https://github.com/llvm/llvm-project/pull/172951