liblinphone注册状态的变化

typedef enum _LinphoneRegistrationState{

LinphoneRegistrationNone,/**<Initial state for registrations */

LinphoneRegistrationProgress,/**<Registration is in progress */

LinphoneRegistrationOk,/**< Registration is successful */

LinphoneRegistrationCleared,/**< Unregistration succeeded */

LinphoneRegistrationFailed/**<Registration failed */

}LinphoneRegistrationState;