octeontx2-af: cn10k: mcs: Support for stats collection

Add mailbox messages to return the resource stats to the
caller. Stats of SecY, SC and SAs as per the macsec standard,
TCAM flow id hits/miss, mailbox to clear the stats are
implemented.

Signed-off-by: Geetha sowjanya <gakula@marvell.com>
Signed-off-by: Ankur Dwivedi <adwivedi@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: Subbaraya Sundeep <sbhatta@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>