bundle: plug leaks in `create_bundle()`
When creating a bundle, we set up a revision walk, but never release
data associated with it. Furthermore, we create a mostly-shallow copy of
that revision walk where we only adapt its pending objects such that we
can reuse the walk. While that copy must not be released, the pending
objects array need to be.
Plug those memory leaks by releasing the revision walk and the pending
objects of the copied revision walk.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>