[llvm] [OFFLOAD] Stricter enforcement of user offload disable (PR #133470)

[via llvm-commits]

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@@ -31,6 +32,12 @@ void initRuntime() {
   if (PM == nullptr)
     PM = new PluginManager();
 
+  if (OffloadPolicy::isOffloadDisabled()) {
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adurang wrote:

It is initialized to good values (0 devices, no plugins loaded, ...) by the constructor. I ran it through our testsuites and didn't see any failure.

https://github.com/llvm/llvm-project/pull/133470