octeontx2-af: Enable inner IPv4 checksum and its error code

This patch enables the inner IPv4 checksum and
defines the error code for Rx inner and outer checksum errors.
Setting ERRCODE as 1 so that CQE descriptor can be embedded
valid checksum error code and the driver can interpret
checksum error as ERRLEV = LID + 1 and ERRCODE = 1.

Signed-off-by: Jerin Jacob <jerinj@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>