In some cases a chain could change from stale to active, but once it's
added to staleChains it would always be deleted once. When the proxier
tries to delete a previously stale but currently active chain, it would
fail and lead to errors, though it won't cause real problem thanks to
kernel's validation.
The commit removes a chain from staleChains if it becomes active.
Signed-off-by: Quan Tian <qtian@vmware.com>
ca8c27c480