[llvm] [XCOFF][obj2yaml] support parsing auxiliary symbols for XCOFF (PR #70642)

[via llvm-commits]

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@@ -52,12 +52,30 @@
 # CHECK32-NEXT:     Type:            0x0
 # CHECK32-NEXT:     StorageClass:    C_EXT
 # CHECK32-NEXT:     NumberOfAuxEntries: 1
+# CHECK32-NEXT:     AuxEntries:
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EsmeYi wrote:

NumberOfAuxEntries was set to 1 but non auxiliary symbol is defined in this case, which was allowed before but will be illegal after this PR. And `aix.yaml` is a basic test for general behavior of xcoff2yaml and I think it would be better to add such test instead of remove the set of `NumberOfAuxEntries: 1` here.

https://github.com/llvm/llvm-project/pull/70642