netfilter: netns ebtables: more cleanup during ebt_unregister_table()

Now that ebt_unregister_table() can be called during netns stop, and module
pinning scheme can't prevent netns stop, do table cleanup by hand.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
index 82e1752..fa108c4 100644
--- a/net/bridge/netfilter/ebtables.c
+++ b/net/bridge/netfilter/ebtables.c
@@ -1209,6 +1209,10 @@
 	mutex_lock(&ebt_mutex);
 	list_del(&table->list);
 	mutex_unlock(&ebt_mutex);
+	EBT_ENTRY_ITERATE(table->private->entries, table->private->entries_size,
+			  ebt_cleanup_entry, NULL);
+	if (table->private->nentries)
+		module_put(table->me);
 	vfree(table->private->entries);
 	if (table->private->chainstack) {
 		for_each_possible_cpu(i)