Add Bluetooth examples

Co-authored-by: Peter Harper <77111776+peterharperuk@users.noreply.github.com>

pico_w/wifi/access_point/dnsserver/dnsserver.h

@@ -0,0 +1,20 @@
+/**
+ * Copyright (c) 2022 Raspberry Pi (Trading) Ltd.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef _DNSSERVER_H_
+#define _DNSSERVER_H_
+
+#include "lwip/ip_addr.h"
+
+typedef struct dns_server_t_ {
+    struct udp_pcb *udp;
+     ip_addr_t ip;
+} dns_server_t;
+
+void dns_server_init(dns_server_t *d, ip_addr_t *ip);
+void dns_server_deinit(dns_server_t *d);
+
+#endif