[llvm] [llvm-objcopy] fix llvm-objcopy replaced failed when the file is modified inplace (PR #121564)

[Fangrui Song via llvm-commits]

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@@ -62,13 +64,13 @@ static Error deepWriteArchive(StringRef ArcName,
                               ArrayRef<NewArchiveMember> NewMembers,
                               SymtabWritingMode WriteSymtab,
                               object::Archive::Kind Kind, bool Deterministic,
-                              bool Thin) {
+                              bool Thin, std::unique_ptr<MemoryBuffer> Buffer) {
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MaskRay wrote:

perhaps `MemoryBufferRef` and drop `include <memory>`

https://github.com/llvm/llvm-project/pull/121564