Add setHostname() method to WiFi

Author: pennam

libraries/WiFi/src/WiFi.cpp

@@ -96,6 +96,11 @@ int arduino::WiFiClass::begin(const char* ssid) {
   return begin(ssid, NULL, ENC_TYPE_NONE);
 }
 
+int arduino::WiFiClass::setHostname(const char* hostname) {
+  wifi_if->set_hostname(hostname);
+  return 1;
+}
+
 //Config Wifi to set Static IP && Disable DHCP
 void arduino::WiFiClass::config(const char* localip, const char* netmask, const char* gateway){
   SocketHelpers::config(IPAddress(localip), dnsIP(0), IPAddress(gateway), IPAddress(netmask));

libraries/WiFi/src/WiFi.h

@@ -75,7 +75,10 @@ class WiFiClass : public MbedSocketClass {
      *        must be between ASCII 32-126 (decimal).
      */
   int begin(const char* ssid, const char* passphrase, wl_enc_type security = ENC_TYPE_UNKNOWN);
-	
+
+  // When using DHCP the hostname provided will be used.
+  int setHostname(const char* hostname);
+
   // Inherit config methods from the parent class
   using MbedSocketClass::config;