[llvm] [Offload] Add device UID (PR #164391)

[Joseph Huber via llvm-commits]

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@@ -1290,6 +1310,14 @@ struct GenericPluginTy {
     return UserDeviceIds.at(DeviceId);
   }
 
+  /// Get the UID for the given device.
+  const char *getDeviceUid(int32_t DeviceId) const {
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jhuber6 wrote:

We really don't need a plugin-level interface into a device property. Users should get a device, then query it from the device.

https://github.com/llvm/llvm-project/pull/164391