If the module is set to absent, read all possible configurations and remove them.
i.e. not just do a 'no switchport', as leaving around other options make
the logic handling harder.
If the user wants to remove switchport, remove all config for the interface
and finally push a 'no switchport'.
Also, I needed to map all possible params from interface regardless if state
is absent or present, so I can later detect what I need to remove in case of absent.
Tetsuya Sodo
Trishna Guha
Dave Thelen
Lindsay Hill
Ricardo Carrillo Cruz