bonding: avoid a warning

drivers/net/bonding/bond_main.c:179:12: warning: ‘disable_netpoll’
defined but not used

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/bonding/bond_main.c

@@ -176,7 +176,9 @@ static int arp_ip_count;
 static int bond_mode	= BOND_MODE_ROUNDROBIN;
 static int xmit_hashtype = BOND_XMIT_POLICY_LAYER2;
 static int lacp_fast;
+#ifdef CONFIG_NET_POLL_CONTROLLER
 static int disable_netpoll = 1;
+#endif
 
 const struct bond_parm_tbl bond_lacp_tbl[] = {
 {	"slow",		AD_LACP_SLOW},