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

[James Henderson via llvm-commits]

https://github.com/jh7370 commented:

@quic-areg, please don't resolve comment threads where I've requested changes: please let me resolve them as a marker that I'm happy with the resolution.

A thought on testing: how do you show that the lines are terminated properly (including a `\r`)?

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