test gdb as it runs qemu simulator

[Tom Tromey]

>> While I would appreciate a fully fleshed out solution, I'm sure that
>> is too much to expect.  I suspect many have done this before me, but
>> none of my many searches have found the blog post (or whatever)
>> which shows how they did it.

Luis> You're right that this has been done before, but the extra
Luis> code/framework required unfortunately never made its way upstream. It
Luis> might still exist in some company's internal repo.

I remembered seeing this before and found this:

https://inbox.sourceware.org/gdb-patches/20231204024634.419445-3-zeck654321@gmail.com/

I filed a bug to track the idea

https://sourceware.org/bugzilla/show_bug.cgi?id=33590

I don't know why that patch didn't land but I think it would be a good
addition.  Perhaps a bit of cleanup would be needed.

Tom