[llvm] [llvm-objcopy] Support SREC output format (PR #75874)

[James Henderson via llvm-commits]

https://github.com/jh7370 approved this pull request.

LGTM. I'll look to merge shortly.

P.S. there's no need to manually squash this as we use the Squash & Merge approach in this project (i.e. squashing happens automatically).

https://github.com/llvm/llvm-project/pull/75874