nailgun-agent can't determine MAX SPEED of some NICs

[Leontii Istomin]

Detailed bug description:
 nailgun-agent can't determine MAX SPEED of intel x710 NIC (screenshot is attached). Therefore we can't automate configuring an environment via Nailgun API and can't see a value of the parameter via Fuel UI.
Steps to reproduce:
 1. Deploy fuel-9.0-mos-401
 2. Boot a node with intel x710 NIC to fuel bootstrap via pxe
 3. Create an env and add the node to the env
 4. Click to cogwheel in front of the node and expand Interfaces section
 5. Find that MAX SPEED is undefined
Expected results:
 see MAX SPEED value
Actual result:
 MAX SPEED = N/A
Reproducibility:
 Each time with intel x710 NIC
Workaround:
 ssh to node and use ethtool
Impact:
 automation and UI user experience
Description of the environment:
 Operation system: -
 Versions of components: -
 Reference architecture: -
 Network model: -
 Related projects installed: -
Additional information:
 -

[Dmitry Pyzhov (dpyzhov)]

Sorry, but I don't see any reason to mark it as high priority. It is inconvenient in some cases but doesn't break anything.

[Alexander Gordeev (a-gordeev)]

s/fuel-agent/nailgun-agent/g

perhaps, rethtool can't determine speed for some reasons https://github.com/openstack/fuel-nailgun-agent/blob/c5f7deaa98c8b137d8d08d8d8c0c2f8406277576/agent#L376-L388