ipvs: initialize tbl->entries after allocation

tbl->entries is not initialized after kmalloc(), therefore
causes an uninit-value warning in ip_vs_lblc_check_expire()
as reported by syzbot.

Reported-by: <syzbot+3dfdea57819073a04f21@syzkaller.appspotmail.com>
Cc: Simon Horman <horms@verge.net.au>
Cc: Julian Anastasov <ja@ssi.bg>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

net/netfilter/ipvs/ip_vs_lblcr.c

@@ -535,6 +535,7 @@ static int ip_vs_lblcr_init_svc(struct ip_vs_service *svc)
 	tbl->counter = 1;
 	tbl->dead = false;
 	tbl->svc = svc;
+	atomic_set(&tbl->entries, 0);
 
 	/*
 	 *    Hook periodic timer for garbage collection