The previous reflist logic would early-exit the loop body if one of the
lists was empty, but that skips the compacting logic entirely.
Instead of doing the early-exit, we can leave a list's ref as nil when
the list end is reached and then flip the comparison result, which will
essentially treat it as being greater than all others. This should
preserve the general behavior without omitting the compaction.
Signed-off-by: Ryan Gonzalez <ryan.gonzalez@collabora.com>