Removed unused "socket.h" interface from WiFi library.

(that was probably an heritage from Ethernet lib)

Author: cmaglie

libraries/WiFi/arch/avr/WiFiClient.cpp

@@ -1,7 +1,6 @@
 extern "C" {
   #include "utility/wl_definitions.h"
   #include "utility/wl_types.h"
-  #include "utility/socket.h"
   #include "string.h"
   #include "utility/debug.h"
 }

libraries/WiFi/arch/avr/utility/socket.h

@@ -1,7 +1,6 @@
 extern "C" {
   #include "utility/wl_definitions.h"
   #include "utility/wl_types.h"
-  #include "utility/socket.h"
   #include "string.h"
   #include "utility/debug.h"
 }

libraries/WiFi/arch/sam/WiFiClient.cpp

@@ -22,6 +22,8 @@
 #define WL_NETWORKS_LIST_MAXNUM	10
 // Maxmium number of socket
 #define	MAX_SOCK_NUM		4
+// Socket not available constant
+#define SOCK_NOT_AVAIL  255
 // Default state value for Wifi state field
 #define NA_STATE -1
 //Maximum number of attempts to establish wifi connection