[llvm] [ELFDebugObjectPlugin] Do not wait for std::future in post-fixup phase in the absent of debug info (PR #178541)

[Stefan Gränitz via llvm-commits]

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+# REQUIRES: native && x86_64-linux
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weliveindetail wrote:

Essentially, this adds coverage for the no-debug-info case right? Can we rename the test to `ELF_no_debug_info.s`?

https://github.com/llvm/llvm-project/pull/178541