[llvm] [Offload] Skip most liboffload tests if no devices (PR #157417)

[Michał Górny via llvm-commits]

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@@ -129,6 +129,9 @@ const std::vector<TestEnvironment::Device> &TestEnvironment::getDevices() {
     }
   }
 
+  if (Devices.size() <= 1)
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mgorny wrote:

I don't really know the code but the `<= 1` looks suspicious here, especially given it's already skipping `OL_PLATFORM_BACKEND_HOST` above. Are you sure it shouldn't be `< 1`? If indeed that is the case, could you add an explanatory comment?

https://github.com/llvm/llvm-project/pull/157417