octeontx2-af: NIX LSO config for TSOv4/v6 offload

Config LSO formats for TSOv4 and TSOv6 offloads.
These formats tell HW which fields in the TCP packet's
headers have to be updated while performing segmentation
offload.

Also report PF/VF drivers the LSO format indices as part
of response to NIX_LF_ALLOC mbox msg. These indices are
used in SQE extension headers while framing SQE for pkt
transmission with TSO offload.

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