batman-adv: report compat_version in version field in case of version mismatch

Reported-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>

net/batman-adv/icmp_socket.c

@@ -217,7 +217,7 @@ static ssize_t bat_socket_write(struct file *file, const char __user *buff,
 
 	if (icmp_packet->version != COMPAT_VERSION) {
 		icmp_packet->msg_type = PARAMETER_PROBLEM;
-		icmp_packet->ttl = COMPAT_VERSION;
+		icmp_packet->version = COMPAT_VERSION;
 		bat_socket_add_packet(socket_client, icmp_packet, packet_len);
 		goto free_skb;
 	}