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

[Ruoyu Qiu via llvm-commits]

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@@ -0,0 +1,33 @@
+# RUN: yaml2obj %s -o %t
+# REQUIRES: arm-registered-target,x86-registered-target
+
+## Check if we can handle without -d
+# RUN: llvm-objdump --mcpu=help %t 2>&1 \
+# RUN:   | FileCheck %s --check-prefixes=CHECK-HELP,CHECK-ARM
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cabbaken wrote:

The pre-existing test file covers `llvm-objdump -d %t --mcpu=help`.
This case verifies that it works without -d.

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