octeontx2-af: Alloc and config NPC MCAM entry at a time

A new mailbox message is added to support allocating a MCAM entry
along with a counter and configuring it in one go. This reduces
the amount of mailbox communication involved in installing a new
MCAM rule.

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