The object describes the method to send the type of telephone number.
gatewayAll The register mode is gateway mode and the register
message contains all the POTS numbers.
gatewaySingle The register mode is gateway mode and every register
message contains only one POTS number.
phoneNumber The register mode is phone mode.
Note: Please configure the object hwSIPRegisterPhoneNumber
after hwSIPRegisterMode has been set to phoneNumber.
This value couldn't be modified unless
h3cSIPRegisterEnable is 'off'.