net/ipn3ke: use control thread to check link status

ipn3ke driver creates a thread to check link status.

Before this patch, pthread_create() is used to create
thread, leaving the new thread unrestrained wrt cpu
affinity.

After this patch, rte_ctrl_thread_create() is used to
create thread. The affinity of the new thread is based
on the CPU affinity retrieved at the time rte_eal_init()
was called, the dataplane and service lcores are then
excluded.

Fixes: 70d6b7f550 ("net/ipn3ke: add representor")
Cc: stable@dpdk.org

Signed-off-by: Andy Pei <andy.pei@intel.com>
Reviewed-by: Rosen Xu <rosen.xu@intel.com>

drivers/net/ipn3ke/ipn3ke_representor.c

@@ -2598,7 +2598,8 @@ ipn3ke_rpst_scan_check(void)
 	int ret;
 
 	if (ipn3ke_rpst_scan_num == 1) {
-		ret = pthread_create(&ipn3ke_rpst_scan_thread,
+		ret = rte_ctrl_thread_create(&ipn3ke_rpst_scan_thread,
+			"ipn3ke scanner",
 			NULL,
 			ipn3ke_rpst_scan_handle_request, NULL);
 		if (ret) {