[llvm] [AVR] Fix parsing & emitting relative jumps (PR #102936)

[via llvm-commits]

aykevl wrote:

GitHub has several ways to merge a PR from the web UI:

* "Create a merge commit"
* "Squash and merge"
* "Rebase and merge"

Of these, only the 2nd is enabled, "squash and merge". That means that from the web UI, it's only possible to squash the two commits together into one and merge that. Which is probably not what you intended!

I've noticed that (apparently) I can squash+merge a PR from the web UI. Didn't know that.
In other words, if you make a new PR with just the first commit (for example), it seems I can merge that one and we can request a backport now.

https://github.com/llvm/llvm-project/pull/102936