Suspend / remove LwM2M device accounts

Our existing IoT gateway device uses Device Management to register with the C8y platform, which creates a device account containing the device credentials.

Two of our use cases involve being able to restrict the device's access to the platform temporarily (disable the account) or permanently (delete the account).

Use a device that registers with the LwM2M device connector, the device is "owned" by the user that registered it and there is no associated device account, as the device uses PSK to authenticate. In this instance, there seems to be no equivalent functionality to suspend or remove the device's access. A mechanism to temporarily suspend or to permanently remove the device's access is required.