[llvm] [llvm-objdump] Print out xcoff file header for xcoff object file with option private-headers (PR #96350)

[James Henderson via llvm-commits]

================
@@ -18,21 +22,29 @@ Sections:
     Flags:           [ STYP_DATA ]
     SectionData:     "0000000000000FC0"
 
-# CHECK32:      ---File Header:
-# CHECK32-NEXT: Magic:              0x1df
-# CHECK32-NEXT: NumberOfSections:   2
-# CHECK32-NEXT: TimeStamp:          None (0)
-# CHECK32-NEXT: SymbolTableOffset:  0x0
-# CHECK32-NEXT: SymbolTableEntries: 0
-# CHECK32-NEXT: OptionalHeaderSize: 0x0
-# CHECK32-NEXT: Flags:              0x0
+# CHECK32:---File Header:
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jh7370 wrote:

```suggestion
#      CHECK32:---File Header:
```
This makes things a little more readable. Same below for the CHECK64 case.

https://github.com/llvm/llvm-project/pull/96350