[llvm] [llvm-objdump] Add triple support to `mcpu=help` (PR #165661)

[James Henderson via llvm-commits]

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@@ -14,3 +14,30 @@ FileHeader:
   Data:            ELFDATA2LSB
   Type:            ET_EXEC
   Machine:         EM_X86_64
+
+# RUN: cp %t a.out
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jh7370 wrote:

These test cases would benefit from some comments to explain what each case is testing specifically. I also think a specific comment for the `rm` line would be appropriate saying why it is being done.

https://github.com/llvm/llvm-project/pull/165661