[llvm] [Offload] Only initialize a plugin if it is needed (PR #92765)

[Joseph Huber via llvm-commits]

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@@ -160,6 +153,27 @@ void PluginManager::registerLib(__tgt_bin_desc *Desc) {
     if (Entry.flags == OMP_REGISTER_REQUIRES)
       PM->addRequirements(Entry.data);
 
+  // Initialize all the plugins that have associated images.
+  for (auto &Plugin : Plugins) {
+    if (Plugin->is_active())
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jhuber6 wrote:

Whether or not the `init` method was called. I couldn't think of a good name for this, it's just a way to control whether or not we can use the plugin to do the actual checking. So, first pass just says "Is this an ELF with a matching platform" second pass says "Does this subarchitecture match".

https://github.com/llvm/llvm-project/pull/92765