net/mlx4_en: Set max rate-limit for a TC

This patch is using the DCB netlink to set rate limit per ETS TC
Values are accepted in Kbps and rounded up to the nearest multiply of 100Mbps.

Signed-off-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>