ipvs: Remove unused macros

They are not used since commit e4ff6751 ("ipvs: add
sync_maxlen parameter for the sync daemon")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

net/netfilter/ipvs/ip_vs_sync.c

@@ -242,9 +242,6 @@ struct ip_vs_sync_thread_data {
       |                    IPVS Sync Connection (1)                   |
 */
 
-#define SYNC_MESG_HEADER_LEN	4
-#define MAX_CONNS_PER_SYNCBUFF	255 /* nr_conns in ip_vs_sync_mesg is 8 bit */
-
 /* Version 0 header */
 struct ip_vs_sync_mesg_v0 {
 	__u8                    nr_conns;