[clang] [HIP][NFC] Refactor managed var codegen (PR #85976)

[Joseph Huber via cfe-commits]

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@@ -1160,9 +1152,8 @@ void CGNVCUDARuntime::createOffloadingEntries() {
 
 // Returns module constructor to be added.
 llvm::Function *CGNVCUDARuntime::finalizeModule() {
+  transformManagedVars();
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jhuber6 wrote:

I'm guessing we also don't have a test for `__managed__` in the external test suite?

https://github.com/llvm/llvm-project/pull/85976