remove unnecessary tls define

src/certs/ca.c

@@ -74,23 +74,15 @@ static const char *iot_https_ca_crt = \
     "CAUw7C29C79Fv1C5qfPrmAESrciIxpg0X40KPMbp1ZWVbd4=\r\n"
     "-----END CERTIFICATE-----\r\n"
 };
-#endif
 
 const char *iot_ca_get() {
-#ifdef SUPPORT_TLS
     return iot_ca_crt;
-#else
-    return NULL;
-#endif
 }
 
 const char *iot_https_ca_get() {
-#ifdef SUPPORT_TLS
     return iot_https_ca_crt;
-#else
-    return NULL;
-#endif
 }
+#endif
 
 #ifdef __cplusplus
 }