[llvm] [Offload] Add `MAX_WORK_GROUP_SIZE` device info query (PR #143718)

[Ross Brunton via llvm-commits]

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@@ -264,13 +266,16 @@ Error olGetDeviceInfoImplDetail(ol_device_handle_t Device,
 
     return "";
   };
-  auto GetInfoXyz = [&](std::vector<std::string> Names) {
-    if (!Device->Device)
-      return ol_dimensions_t{0, 0, 0};
+  auto GetInfoXyz = [&](std::vector<std::string> Names) -> Error {
+    if (Device == OffloadContext::get().HostDevice())
+      return ReturnValue(ol_dimensions_t{0u, 0u, 0u});
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RossBrunton wrote:

What would be the value of `T`?

https://github.com/llvm/llvm-project/pull/143718