poecli restore invalidates any saved config

[rothcar]

To reproduce:

1. disable a port
2. execute poecli restore
3. note that the port is no longer disabled.

The restore function should ideally restore port configuration from the last saved running-config.

[leonchiang]

The "poecli restore" command make an platform/poeChip restore, that will apply our platform settings (include all port Enable), we'll fix this up by remove relate settings in platform codes to avoid enabling ports. (same issue: #11 )
If you need an config restore, we'll add new cli command "poecli cfg" to implement.