octeontx2-af: Fix mcs stats register address

This patch adds the miss mcs stats register
for mcs supported platforms.

Fixes: 9312150a

 ("octeontx2-af: cn10k: mcs: Support for stats collection")
Signed-off-by: Geetha sowjanya <gakula@marvell.com>
Reviewed-by: Wojciech Drewek <wojciech.drewek@intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>