inhibit: fix compatibility with changes in rebase
Because we compute the obsolete revisions before calling
_computeobsoletenotrebased lifting the inhibition stopped working
since 8a8ee8338e6 in core. This patch makes it work again.
inhibit: fix _filterpublic
Before this patch, _filterpublic would always filter rep._obsinhibit and not
its "nodes" argument. Fortunately, we always called it with repo._obsinhibit as
its "nodes" argument!