Refactor eos_cli_config_gen switchport data models

[ClausHolbechArista]

ethernet_interfaces(and probably others):

• All/most switchport xxx commands are cut off like native_vlan and vlans which should have been switchport.trunk.native_vlan and switchport.access.vlan & switchport.trunk.allowed_vlans.
• We have a type key which is abstracting too much in the config

[github-actions]

This issue is stale because it has been open 90 days with no activity. The issue will be reviewed by a maintainer and may be closed

[github-actions]

This issue is stale because it has been open 90 days with no activity. The issue will be reviewed by a maintainer and may be closed

[ClausHolbechArista]

This should be implemented in eos_cli_config_gen immediately. It should support the full switchport syntax, and should not be combined with the existing mode, vlans, native_vlan, type and maybe other keys.
Once implemented, we can switch the output of eos_designs in 5.0 and deprecate the old keys.

Since type also affects subinterfaces etc, we may have to add a couple of other models before we can remove mode.