get_device_warnings is gone; netOrk names the warnings from facts
(netOrk #1111). lldpd and the pending updates were already facts
(get_packages, get_available_updates). The subscription is now
get_licenses() from napalm-device-types 4.14's LicenseMixin: one
pve-subscription entry, the API status mapped to a LicenseStatus.
The old check compared against "NotFound" while the API answers
"notfound" (seen on all four nodes), so it never fired; the mapping is
case-insensitive.
