ArduinoIoTCloudTCP: use generic Cert class instead of ECCX08CertClass

Author: pennam

src/ArduinoIoTCloudTCP.cpp

@@ -233,7 +233,7 @@ int ArduinoIoTCloudTCP::begin(bool const enable_watchdog, String brokerAddress,
     return 0;
   }
   _sslClient.setClient(_connection->getClient());
-  _sslClient.setEccSlot(static_cast<int>(ECCX08Slot::Key), _eccx08_cert.bytes(), _eccx08_cert.length());
+  _sslClient.setEccSlot(static_cast<int>(CryptoSlot::Key), _cert.bytes(), _cert.length());
   #elif defined(BOARD_ESP)
   _sslClient.setInsecure();
   #endif

src/ArduinoIoTCloudTCP.h

@@ -28,14 +28,12 @@
 
 #ifdef BOARD_HAS_ECCX08
   #include "tls/BearSSLClient.h"
-  #include "tls/utility/ECCX08Cert.h"
   #include "tls/utility/CryptoUtil.h"
 #elif defined(BOARD_ESP)
   #include <WiFiClientSecure.h>
 #endif
 
 #ifdef BOARD_HAS_OFFLOADED_ECCX08
-#include "tls/utility/ECCX08Cert.h"
 #include "tls/utility/CryptoUtil.h"
 #include <WiFiSSLClient.h>
 #endif
@@ -135,11 +133,11 @@ class ArduinoIoTCloudTCP: public ArduinoIoTCloudClass
     bool _mqtt_data_request_retransmit;
 
     #if defined(BOARD_HAS_ECCX08)
-    ECCX08CertClass _eccx08_cert;
+    ArduinoIoTCloudCertClass _cert;
     BearSSLClient _sslClient;
     CryptoUtil _crypto;
     #elif defined(BOARD_HAS_OFFLOADED_ECCX08)
-    ECCX08CertClass _eccx08_cert;
+    ArduinoIoTCloudCertClass _cert;
     WiFiBearSSLClient _sslClient;
     CryptoUtil _crypto;
     #elif defined(BOARD_ESP)