Consider using setsockopt to set and limit a socket's SO_MAX_PACING_RATE

[stephen-soltesz]

@mattmathis reported that it's possible to set the max pacing rate for a socket using setsockopt. This could be done at the same time BBR is enabled . This could be a way of enforcing per-connection rate limits (e.g. 2.5Gbps) in addition to whole-machine limits with the TxController.

https://lxr.missinglinkelectronics.com/linux/net/core/sock.c#L1164