Fix typo s/assgined/assigned/
Fix typo on var name
Pass parent interface to link_interface_to_vlans
Simplify a bit the logic
Consider parent mtu when it's set instead of default one
Set vlanifs early and use it on more places to simplify logic
When reset parent to default mtu, deal with all VLANs too
When parent is not assigned, reset it and all vlans without mtu set to default
Check if MTU is already with correct value before change it
Fix logic inversion from 126ff5b264
Be consistent on vlan checks