mlx5en: Implement support for internal queues, IQ.

Internal send queues are regular sendqueues which are reserved for WQE commands
towards the hardware and firmware. These queues typically carry res

mlx5en: Implement support for internal queues, IQ.

Internal send queues are regular sendqueues which are reserved for WQE commands
towards the hardware and firmware. These queues typically carry resync
information for ongoing TLS RX connections and when changing schedule queues
for rate limited connections.

The internal queue, IQ, code is more or less a stripped down copy
of the existing SQ managing code with exception of:

1) An optional single segment memory buffer which can be read or
written as a whole by the hardware, may be provided.
2) An optional completion callback for all transmit operations, may
be provided.
3) Does not support mbufs.

Sponsored by: NVIDIA Networking

(cherry picked from commit 694263572f1bdf545199fcfb0853b93eb0dd0644)

show more ...