(Re)implement patty_ax25_sock_reset()

Begin to reimplement patty_ax25_sock_reset() to follow the AX.25 v2.2
Specification, Section 6.5 "Resetting Procedure" indications to set V(S)
and V(R) to 0

include/patty/ax25/sock.h

@@ -96,6 +96,8 @@ patty_ax25_sock *patty_ax25_sock_new(enum patty_ax25_proto proto,
 
 void patty_ax25_sock_destroy(patty_ax25_sock *sock);
 
+int patty_ax25_sock_reset(patty_ax25_sock *sock);
+
 int patty_ax25_sock_upgrade(patty_ax25_sock *sock,
                             enum patty_ax25_version version);
 

src/server.c

@@ -1275,7 +1275,7 @@ static int handle_dm(patty_ax25_server *server,
         goto error_client_by_sock;
     }
 
-    patty_ax25_sock_init(sock);
+    patty_ax25_sock_reset(sock);
 
     return respond_connect(client, -1, ECONNREFUSED);
 
@@ -1423,7 +1423,7 @@ static int handle_xid(patty_ax25_server *server,
                 goto error_client_by_sock;
             }
 
-            patty_ax25_sock_init(remote);
+            patty_ax25_sock_reset(remote);
 
             return respond_connect(client, -1, errno);
         }

src/sock.c

@@ -176,6 +176,16 @@ void patty_ax25_sock_destroy(patty_ax25_sock *sock) {
     free(sock);
 }
 
+/*
+ * AX.25 v2.2 Specification, Section 6.5 "Resetting Procedure"
+ */
+int patty_ax25_sock_reset(patty_ax25_sock *sock) {
+    sock->seq_send = 0;
+    sock->seq_recv = 0;
+
+    return 0;
+}
+
 int patty_ax25_sock_upgrade(patty_ax25_sock *sock,
                             enum patty_ax25_version version) {
     if (sock->version >= version) {