octeontx2-af: Support to get NIX HW constants from AF

This patch adds reading HW limits like number of Rx/Tx stats,
number of queue IRQs supported per NIX LF from AF registers
and sync them to PF/VF.

Signed-off-by: Kiran Kumar <kirankumark@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>