Add the certificate to the certificate chain that is being used by the current config. 
- 参数
 - 
  
    | config | [IN] TLS link configuration  | 
    | cert | [IN] Certificate to be added  | 
    | isClone | [IN] Indicates whether deep copy is required. The options are true and false.  | 
  
   
- 返回值
 - 
  
    | HITLS_SUCCESS,if | successful. For details about other error codes, see hitls_error.h.  |