tools: replace add with xadd (#3518)

resolve #3481
replace add with xadd for more tools.
diff --git a/tools/tcpsynbl.py b/tools/tcpsynbl.py
index c24eb96..93cef4b 100755
--- a/tools/tcpsynbl.py
+++ b/tools/tcpsynbl.py
@@ -33,7 +33,7 @@
     backlog_key_t key = {};
     key.backlog = sk->sk_max_ack_backlog;
     key.slot = bpf_log2l(sk->sk_ack_backlog);
-    dist.increment(key);
+    dist.atomic_increment(key);
 
     return 0;
 };