[llvm] [Offload] Implement `olShutDown` (PR #144055)

[Ross Brunton via llvm-commits]

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@@ -197,8 +195,10 @@ Error olInit_impl() {
   std::lock_guard<std::mutex> Lock{OffloadContextValMutex};
 
   std::optional<Error> InitResult;
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RossBrunton wrote:

I was trying to work around the fact that all errors must be checked. But it turns out it's simple enough to just shift the order logic around to avoid it.

https://github.com/llvm/llvm-project/pull/144055