octeontx2-af: Exact match scan from kex profile

CN10KB silicon supports exact match table. Scanning KEX
profile should check for exact match feature is enabled
and then set profile masks properly.

These kex profile masks are required to configure NPC
MCAM drop rules. If there is a miss in exact match table,
these drop rules will drop those packets.

Signed-off-by: Ratheesh Kannoth <rkannoth@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>