[llvm] [llvm-readobj][ELF] Fix broken JSON output with --dynamic-table (PR #95976)

[Paul Kirth via llvm-commits]

ilovepi wrote:

Can you include a snippet in the commit message that shows how the output is changing? We've done that for patches like this in the past, and it helps make clear what the new behavior is.

https://github.com/llvm/llvm-project/pull/95976