Cleanup handling of non-standard functions in lwIP

- itoa
- strnicmp, stricmp/strcasecmp
- strnstr
Related to patch #9115: httpd.c: strcasecmp for GCC and stricmp for Windows

src/apps/netbiosns/netbiosns.c

@@ -46,6 +46,7 @@
 
 #if LWIP_IPV4 && LWIP_UDP  /* don't build if not configured for use in lwipopts.h */
 
+#include "lwip/def.h"
 #include "lwip/udp.h"
 #include "lwip/netif.h"
 
@@ -270,7 +271,7 @@ netbiosns_recv(void *arg, struct udp_pcb *upcb, struct pbuf *p, const ip_addr_t
         /* decode the NetBIOS name */
         netbiosns_name_decode((char*)(netbios_name_hdr->encname), netbios_name, sizeof(netbios_name));
         /* if the packet is for us */
-        if (NETBIOS_STRCMP(netbios_name, NETBIOS_LOCAL_NAME) == 0) {
+        if (lwip_strnicmp(netbios_name, NETBIOS_LOCAL_NAME, sizeof(NETBIOS_LOCAL_NAME)) == 0) {
           struct pbuf *q;
           struct netbios_resp *resp;