Comment 0 for bug 2070314

Netplan currently supports a subset of netdev feature flags related to stateless offload:

https://github.com/canonical/netplan/blob/b9730281029ce7ebd2415af736bf02e6763725d9/src/parse.c#L2962-L2968
https://github.com/canonical/netplan/blob/b9730281029ce7ebd2415af736bf02e6763725d9/examples/offload.yaml#L5-L11

In order to leverage TC state offload to hardware some NICs (like ConnectX, Bluefield etc.) support the `hw-tc-offload` feature flag.

https://github.com/torvalds/linux/blob/55027e689933ba2e64f3d245fb1ff185b3e7fc81/net/ethtool/common.c#L63-L63
```
const char netdev_features_strings[NETDEV_FEATURE_COUNT][ETH_GSTRING_LEN] = {
// ...
 [NETIF_F_HW_TC_BIT] = "hw-tc-offload",
// ...
```

https://github.com/torvalds/linux/blob/55027e689933ba2e64f3d245fb1ff185b3e7fc81/include/linux/netdev_features.h#L75
```
 NETIF_F_HW_TC_BIT, /* Offload TC infrastructure */
```

https://github.com/torvalds/linux/commit/1c78c64e9c6f43a490427d55cd2d213b7c6795c1 (commit introducing the feature).

The result of having this setting exposed in netplan (per device) should be equivalent to running the following command on a netdev:

https://docs.nvidia.com/networking/display/bluefielddpuosv460/virtual+switch+on+dpu#src-2571331481_VirtualSwitchonDPU-EnablingOVSHWOffloading

ethtool -K <PF> hw-tc-offload on

It would be good if netplan supported this option which would alleviate the need for ad-hoc scripts enabling it on a per-device basis.