Fix crashing issues with RSSI

Author: sandeepmistry

src/WiFi.cpp

@@ -259,6 +259,7 @@ int WiFiClass::init()
 	_gateway = 0;
 	_dhcp = 1;
 	_resolve = 0;
+	_remoteMacAddress = 0;
 	memset(_client, 0, sizeof(WiFiClient *) * TCP_SOCK_MAX);
 
 	// Initialize IO expander LED control (rev A then rev B)..
@@ -696,7 +697,11 @@ int32_t WiFiClass::RSSI()
 		m2m_wifi_handle_events(NULL);
 	}
 
-	return _resolve;
+	int32_t rssi = _resolve;
+
+	_resolve = 0;
+
+	return rssi;
 }
 
 int8_t WiFiClass::scanNetworks()