Currently LSO formats setup initially are expected to be
compile time constants and start from 0.
Change the logic in slow and fast path so that LSO format indexes
are only determined runtime.
Fixes: 3b635472a998 ("net/octeontx2: support TSO offload")
Cc: stable@dpdk.org
Signed-off-by: Nithin Dabilpuram <ndabilpuram@marvell.com>