[lld] [lld][COFF] Fix: Merge `.drectve` sections in ObjFile::readSections (PR #86380)

[Alexandre Ganea via llvm-commits]

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aganea wrote:

We tend to prefer textual files in LLVM as much as possible. Can you craft such an input with multiple directive sections instead? See https://github.com/llvm/llvm-project/blob/main/lld/test/COFF/gfids-export.s for an example, which uses `llvm-mc` to create the input from the current test file.

https://github.com/llvm/llvm-project/pull/86380