netfilter: nf_tables: Eliminate duplicated code in nf_tables_table_enable()

If something fails in nf_tables_table_enable(), it unregisters the
chains. But the rollback code is the same as nf_tables_table_disable()
almostly, except there is one counter check.  Now create one wrapper
function to eliminate the duplicated codes.

Signed-off-by: Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

path: root/net/8021q/vlanproc.h

#ifndef __BEN_VLAN_PROC_INC__
#define __BEN_VLAN_PROC_INC__

#ifdef CONFIG_PROC_FS
struct net;

int vlan_proc_init(struct net *net);
void vlan_proc_rem_dev(struct net_device *vlandev);
int vlan_proc_add_dev(struct net_device *vlandev);
void vlan_proc_cleanup(struct net *net);

#else /* No CONFIG_PROC_FS */

#define vlan_proc_init(net)	(0)
#define vlan_proc_cleanup(net)	do {} while (0)
#define vlan_proc_add_dev(dev)	({(void)(dev), 0; })
#define vlan_proc_rem_dev(dev)	do {} while (0)
#endif

#endif /* !(__BEN_VLAN_PROC_INC__) */